diff --git a/src/interfaces/node.cpp b/src/interfaces/node.cpp
index 04a9fda00..d3b728831 100644
--- a/src/interfaces/node.cpp
+++ b/src/interfaces/node.cpp
@@ -1,365 +1,368 @@
 // Copyright (c) 2018 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <interfaces/node.h>
 
 #include <addrdb.h>
 #include <banman.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <config.h>
 #include <init.h>
 #include <interfaces/chain.h>
 #include <interfaces/handler.h>
 #include <interfaces/wallet.h>
 #include <net.h>
 #include <net_processing.h>
 #include <netaddress.h>
 #include <netbase.h>
 #include <node/context.h>
 #include <node/ui_interface.h>
 #include <policy/fees.h>
 #include <policy/settings.h>
 #include <primitives/block.h>
 #include <rpc/server.h>
 #include <shutdown.h>
 #include <support/allocators/secure.h>
 #include <sync.h>
 #include <txmempool.h>
 #include <util/ref.h>
 #include <util/system.h>
 #include <util/translation.h>
 #include <validation.h>
 #include <warnings.h>
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <univalue.h>
 
 #include <boost/signals2/signal.hpp>
 
 class HTTPRPCRequestProcessor;
 class CWallet;
 fs::path GetWalletDir();
 std::vector<fs::path> ListWalletDir();
 std::vector<std::shared_ptr<CWallet>> GetWallets();
 std::shared_ptr<CWallet> LoadWallet(const CChainParams &chainParams,
                                     interfaces::Chain &chain,
                                     const std::string &name,
                                     bilingual_str &error,
                                     std::vector<bilingual_str> &warnings);
 WalletCreationStatus CreateWallet(const CChainParams &params,
                                   interfaces::Chain &chain,
                                   const SecureString &passphrase,
                                   uint64_t wallet_creation_flags,
                                   const std::string &name, bilingual_str &error,
                                   std::vector<bilingual_str> &warnings,
                                   std::shared_ptr<CWallet> &result);
 std::unique_ptr<interfaces::Handler>
 HandleLoadWallet(interfaces::Node::LoadWalletFn load_wallet);
 
 namespace interfaces {
 
 namespace {
 
     class NodeImpl : public Node {
     public:
         NodeImpl(NodeContext *context) { setContext(context); }
         void initLogging() override { InitLogging(*Assert(m_context->args)); }
         void initParameterInteraction() override {
             InitParameterInteraction(*Assert(m_context->args));
         }
         std::string getWarnings() override { return GetWarnings(true); }
         bool baseInitialize(Config &config) override {
             return AppInitBasicSetup(gArgs) &&
                    AppInitParameterInteraction(config, gArgs) &&
                    AppInitSanityChecks() && AppInitLockDataDirectory();
         }
         bool
         appInitMain(Config &config, RPCServer &rpcServer,
                     HTTPRPCRequestProcessor &httpRPCRequestProcessor) override {
             m_context->chain = MakeChain(*m_context, config.GetChainParams());
             return AppInitMain(config, rpcServer, httpRPCRequestProcessor,
                                *m_context);
         }
         void appShutdown() override {
             Interrupt(*m_context);
             Shutdown(*m_context);
         }
         void startShutdown() override { StartShutdown(); }
         bool shutdownRequested() override { return ShutdownRequested(); }
         void mapPort(bool use_upnp) override {
             if (use_upnp) {
                 StartMapPort();
             } else {
                 InterruptMapPort();
                 StopMapPort();
             }
         }
         bool getProxy(Network net, proxyType &proxy_info) override {
             return GetProxy(net, proxy_info);
         }
         size_t getNodeCount(CConnman::NumConnections flags) override {
             return m_context->connman ? m_context->connman->GetNodeCount(flags)
                                       : 0;
         }
         bool getNodesStats(NodesStats &stats) override {
             stats.clear();
 
             if (m_context->connman) {
                 std::vector<CNodeStats> stats_temp;
                 m_context->connman->GetNodeStats(stats_temp);
 
                 stats.reserve(stats_temp.size());
                 for (auto &node_stats_temp : stats_temp) {
                     stats.emplace_back(std::move(node_stats_temp), false,
                                        CNodeStateStats());
                 }
 
                 // Try to retrieve the CNodeStateStats for each node.
                 TRY_LOCK(::cs_main, lockMain);
                 if (lockMain) {
                     for (auto &node_stats : stats) {
                         std::get<1>(node_stats) =
                             GetNodeStateStats(std::get<0>(node_stats).nodeid,
                                               std::get<2>(node_stats));
                     }
                 }
                 return true;
             }
             return false;
         }
         bool getBanned(banmap_t &banmap) override {
             if (m_context->banman) {
                 m_context->banman->GetBanned(banmap);
                 return true;
             }
             return false;
         }
         bool ban(const CNetAddr &net_addr, int64_t ban_time_offset) override {
             if (m_context->banman) {
                 m_context->banman->Ban(net_addr, ban_time_offset);
                 return true;
             }
             return false;
         }
         bool unban(const CSubNet &ip) override {
             if (m_context->banman) {
                 m_context->banman->Unban(ip);
                 return true;
             }
             return false;
         }
         bool disconnectByAddress(const CNetAddr &net_addr) override {
             if (m_context->connman) {
                 return m_context->connman->DisconnectNode(net_addr);
             }
             return false;
         }
         bool disconnectById(NodeId id) override {
             if (m_context->connman) {
                 return m_context->connman->DisconnectNode(id);
             }
             return false;
         }
         int64_t getTotalBytesRecv() override {
             return m_context->connman ? m_context->connman->GetTotalBytesRecv()
                                       : 0;
         }
         int64_t getTotalBytesSent() override {
             return m_context->connman ? m_context->connman->GetTotalBytesSent()
                                       : 0;
         }
         size_t getMempoolSize() override {
             return m_context->mempool ? m_context->mempool->size() : 0;
         }
         size_t getMempoolDynamicUsage() override {
             return m_context->mempool ? m_context->mempool->DynamicMemoryUsage()
                                       : 0;
         }
         bool getHeaderTip(int &height, int64_t &block_time) override {
             LOCK(::cs_main);
             if (::pindexBestHeader) {
                 height = ::pindexBestHeader->nHeight;
                 block_time = ::pindexBestHeader->GetBlockTime();
                 return true;
             }
             return false;
         }
         int getNumBlocks() override {
             LOCK(::cs_main);
             return ::ChainActive().Height();
         }
         BlockHash getBestBlockHash() override {
             const CBlockIndex *tip =
                 WITH_LOCK(::cs_main, return ::ChainActive().Tip());
             return tip ? tip->GetBlockHash()
                        : Params().GenesisBlock().GetHash();
         }
         int64_t getLastBlockTime() override {
             LOCK(::cs_main);
             if (::ChainActive().Tip()) {
                 return ::ChainActive().Tip()->GetBlockTime();
             }
             // Genesis block's time of current network
             return Params().GenesisBlock().GetBlockTime();
         }
         double getVerificationProgress() override {
             const CBlockIndex *tip;
             {
                 LOCK(::cs_main);
                 tip = ::ChainActive().Tip();
             }
             return GuessVerificationProgress(Params().TxData(), tip);
         }
         bool isInitialBlockDownload() override {
             return ::ChainstateActive().IsInitialBlockDownload();
         }
         bool getReindex() override { return ::fReindex; }
         bool getImporting() override { return ::fImporting; }
         void setNetworkActive(bool active) override {
             if (m_context->connman) {
                 m_context->connman->SetNetworkActive(active);
             }
         }
         bool getNetworkActive() override {
             return m_context->connman && m_context->connman->GetNetworkActive();
         }
         CFeeRate estimateSmartFee() override {
             return m_context->mempool ? m_context->mempool->estimateFee()
                                       : CFeeRate();
         }
         CFeeRate getDustRelayFee() override { return ::dustRelayFee; }
         UniValue executeRpc(Config &config, const std::string &command,
                             const UniValue &params,
                             const std::string &uri) override {
             JSONRPCRequest req(m_context_ref);
             req.params = params;
             req.strMethod = command;
             req.URI = uri;
             return ::tableRPC.execute(config, req);
         }
         std::vector<std::string> listRpcCommands() override {
             return ::tableRPC.listCommands();
         }
         void rpcSetTimerInterfaceIfUnset(RPCTimerInterface *iface) override {
             RPCSetTimerInterfaceIfUnset(iface);
         }
         void rpcUnsetTimerInterface(RPCTimerInterface *iface) override {
             RPCUnsetTimerInterface(iface);
         }
         bool getUnspentOutput(const COutPoint &output, Coin &coin) override {
             LOCK(::cs_main);
             return ::ChainstateActive().CoinsTip().GetCoin(output, coin);
         }
         std::string getWalletDir() override { return GetWalletDir().string(); }
         std::vector<std::string> listWalletDir() override {
             std::vector<std::string> paths;
             for (auto &path : ListWalletDir()) {
                 paths.push_back(path.string());
             }
             return paths;
         }
         std::vector<std::unique_ptr<Wallet>> getWallets() override {
             std::vector<std::unique_ptr<Wallet>> wallets;
             for (auto &client : m_context->chain_clients) {
                 auto client_wallets = client->getWallets();
                 std::move(client_wallets.begin(), client_wallets.end(),
                           std::back_inserter(wallets));
             }
             return wallets;
         }
         std::unique_ptr<Wallet>
         loadWallet(const CChainParams &params, const std::string &name,
                    bilingual_str &error,
                    std::vector<bilingual_str> &warnings) const override {
             return MakeWallet(
                 LoadWallet(params, *m_context->chain, name, error, warnings));
         }
         std::unique_ptr<Wallet>
         createWallet(const CChainParams &params, const SecureString &passphrase,
                      uint64_t wallet_creation_flags, const std::string &name,
                      bilingual_str &error, std::vector<bilingual_str> &warnings,
                      WalletCreationStatus &status) override {
             std::shared_ptr<CWallet> wallet;
             status = CreateWallet(params, *m_context->chain, passphrase,
                                   wallet_creation_flags, name, error, warnings,
                                   wallet);
             return MakeWallet(wallet);
         }
         std::unique_ptr<Handler> handleInitMessage(InitMessageFn fn) override {
             return MakeHandler(::uiInterface.InitMessage_connect(fn));
         }
         std::unique_ptr<Handler> handleMessageBox(MessageBoxFn fn) override {
             return MakeHandler(::uiInterface.ThreadSafeMessageBox_connect(fn));
         }
         std::unique_ptr<Handler> handleQuestion(QuestionFn fn) override {
             return MakeHandler(::uiInterface.ThreadSafeQuestion_connect(fn));
         }
         std::unique_ptr<Handler>
         handleShowProgress(ShowProgressFn fn) override {
             return MakeHandler(::uiInterface.ShowProgress_connect(fn));
         }
         std::unique_ptr<Handler> handleLoadWallet(LoadWalletFn fn) override {
             return HandleLoadWallet(std::move(fn));
         }
         std::unique_ptr<Handler> handleNotifyNumConnectionsChanged(
             NotifyNumConnectionsChangedFn fn) override {
             return MakeHandler(
                 ::uiInterface.NotifyNumConnectionsChanged_connect(fn));
         }
         std::unique_ptr<Handler> handleNotifyNetworkActiveChanged(
             NotifyNetworkActiveChangedFn fn) override {
             return MakeHandler(
                 ::uiInterface.NotifyNetworkActiveChanged_connect(fn));
         }
         std::unique_ptr<Handler>
         handleNotifyAlertChanged(NotifyAlertChangedFn fn) override {
             return MakeHandler(::uiInterface.NotifyAlertChanged_connect(fn));
         }
         std::unique_ptr<Handler>
         handleBannedListChanged(BannedListChangedFn fn) override {
             return MakeHandler(::uiInterface.BannedListChanged_connect(fn));
         }
         std::unique_ptr<Handler>
         handleNotifyBlockTip(NotifyBlockTipFn fn) override {
             return MakeHandler(::uiInterface.NotifyBlockTip_connect(
                 [fn](SynchronizationState sync_state,
                      const CBlockIndex *block) {
-                    fn(sync_state, block->GetBlockHash(), block->nHeight,
-                       block->GetBlockTime(),
+                    fn(sync_state,
+                       BlockTip{block->nHeight, block->GetBlockTime(),
+                                block->GetBlockHash()},
                        GuessVerificationProgress(Params().TxData(), block));
                 }));
         }
         std::unique_ptr<Handler>
         handleNotifyHeaderTip(NotifyHeaderTipFn fn) override {
             /* verification progress is unused when a header was received */
             return MakeHandler(::uiInterface.NotifyHeaderTip_connect(
                 [fn](SynchronizationState sync_state,
                      const CBlockIndex *block) {
-                    fn(sync_state, block->GetBlockHash(), block->nHeight,
-                       block->GetBlockTime(), 0);
+                    fn(sync_state,
+                       BlockTip{block->nHeight, block->GetBlockTime(),
+                                block->GetBlockHash()},
+                       0);
                 }));
         }
         NodeContext *context() override { return m_context; }
         void setContext(NodeContext *context) override {
             m_context = context;
             if (context) {
                 m_context_ref.Set(*context);
             } else {
                 m_context_ref.Clear();
             }
         }
         NodeContext *m_context{nullptr};
         util::Ref m_context_ref{m_context};
     };
 } // namespace
 
 std::unique_ptr<Node> MakeNode(NodeContext *context) {
     return std::make_unique<NodeImpl>(context);
 }
 
 } // namespace interfaces
diff --git a/src/interfaces/node.h b/src/interfaces/node.h
index ed4160a78..3bf7668e8 100644
--- a/src/interfaces/node.h
+++ b/src/interfaces/node.h
@@ -1,266 +1,274 @@
 // Copyright (c) 2018 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_INTERFACES_NODE_H
 #define BITCOIN_INTERFACES_NODE_H
 
 #include <amount.h>     // For Amount
 #include <net.h>        // For CConnman::NumConnections
 #include <net_types.h>  // For banmap_t
 #include <netaddress.h> // For Network
 
 #include <support/allocators/secure.h> // For SecureString
 
 #include <cstddef>
 #include <cstdint>
 #include <functional>
 #include <memory>
 #include <string>
 #include <tuple>
 #include <vector>
 
 class BanMan;
 class CCoinControl;
 class CFeeRate;
 struct CNodeStateStats;
 struct CNodeStats;
 class Coin;
 class Config;
 class HTTPRPCRequestProcessor;
 struct NodeContext;
 class proxyType;
 class RPCServer;
 class RPCTimerInterface;
 enum class SynchronizationState;
 class UniValue;
 enum class WalletCreationStatus;
 struct bilingual_str;
 
 namespace interfaces {
 class Handler;
 class Wallet;
+struct BlockTip;
 
 //! Top-level interface for a bitcoin node (bitcoind process).
 class Node {
 public:
     virtual ~Node() {}
 
     //! Init logging.
     virtual void initLogging() = 0;
 
     //! Init parameter interaction.
     virtual void initParameterInteraction() = 0;
 
     //! Get warnings.
     virtual std::string getWarnings() = 0;
 
     //! Initialize app dependencies.
     virtual bool baseInitialize(Config &config) = 0;
 
     //! Start node.
     virtual bool
     appInitMain(Config &config, RPCServer &rpcServer,
                 HTTPRPCRequestProcessor &httpRPCRequestProcessor) = 0;
 
     //! Stop node.
     virtual void appShutdown() = 0;
 
     //! Start shutdown.
     virtual void startShutdown() = 0;
 
     //! Return whether shutdown was requested.
     virtual bool shutdownRequested() = 0;
 
     //! Map port.
     virtual void mapPort(bool use_upnp) = 0;
 
     //! Get proxy.
     virtual bool getProxy(Network net, proxyType &proxy_info) = 0;
 
     //! Get number of connections.
     virtual size_t getNodeCount(CConnman::NumConnections flags) = 0;
 
     //! Get stats for connected nodes.
     using NodesStats =
         std::vector<std::tuple<CNodeStats, bool, CNodeStateStats>>;
     virtual bool getNodesStats(NodesStats &stats) = 0;
 
     //! Get ban map entries.
     virtual bool getBanned(banmap_t &banmap) = 0;
 
     //! Ban node.
     virtual bool ban(const CNetAddr &net_addr, int64_t ban_time_offset) = 0;
 
     //! Unban node.
     virtual bool unban(const CSubNet &ip) = 0;
 
     //! Disconnect node by address.
     virtual bool disconnectByAddress(const CNetAddr &net_addr) = 0;
 
     //! Disconnect node by id.
     virtual bool disconnectById(NodeId id) = 0;
 
     //! Get total bytes recv.
     virtual int64_t getTotalBytesRecv() = 0;
 
     //! Get total bytes sent.
     virtual int64_t getTotalBytesSent() = 0;
 
     //! Get mempool size.
     virtual size_t getMempoolSize() = 0;
 
     //! Get mempool dynamic usage.
     virtual size_t getMempoolDynamicUsage() = 0;
 
     //! Get header tip height and time.
     virtual bool getHeaderTip(int &height, int64_t &block_time) = 0;
 
     //! Get num blocks.
     virtual int getNumBlocks() = 0;
 
     //! Get best block hash.
     virtual BlockHash getBestBlockHash() = 0;
 
     //! Get last block time.
     virtual int64_t getLastBlockTime() = 0;
 
     //! Get verification progress.
     virtual double getVerificationProgress() = 0;
 
     //! Is initial block download.
     virtual bool isInitialBlockDownload() = 0;
 
     //! Get reindex.
     virtual bool getReindex() = 0;
 
     //! Get importing.
     virtual bool getImporting() = 0;
 
     //! Set network active.
     virtual void setNetworkActive(bool active) = 0;
 
     //! Get network active.
     virtual bool getNetworkActive() = 0;
 
     //! Estimate smart fee.
     virtual CFeeRate estimateSmartFee() = 0;
 
     //! Get dust relay fee.
     virtual CFeeRate getDustRelayFee() = 0;
 
     //! Execute rpc command.
     virtual UniValue executeRpc(Config &config, const std::string &command,
                                 const UniValue &params,
                                 const std::string &uri) = 0;
 
     //! List rpc commands.
     virtual std::vector<std::string> listRpcCommands() = 0;
 
     //! Set RPC timer interface if unset.
     virtual void rpcSetTimerInterfaceIfUnset(RPCTimerInterface *iface) = 0;
 
     //! Unset RPC timer interface.
     virtual void rpcUnsetTimerInterface(RPCTimerInterface *iface) = 0;
 
     //! Get unspent outputs associated with a transaction.
     virtual bool getUnspentOutput(const COutPoint &output, Coin &coin) = 0;
 
     //! Return default wallet directory.
     virtual std::string getWalletDir() = 0;
 
     //! Return available wallets in wallet directory.
     virtual std::vector<std::string> listWalletDir() = 0;
 
     //! Return interfaces for accessing wallets (if any).
     virtual std::vector<std::unique_ptr<Wallet>> getWallets() = 0;
 
     //! Attempts to load a wallet from file or directory.
     //! The loaded wallet is also notified to handlers previously registered
     //! with handleLoadWallet.
     virtual std::unique_ptr<Wallet>
     loadWallet(const CChainParams &params, const std::string &name,
                bilingual_str &error,
                std::vector<bilingual_str> &warnings) const = 0;
 
     //! Create a wallet from file
     virtual std::unique_ptr<Wallet>
     createWallet(const CChainParams &params, const SecureString &passphrase,
                  uint64_t wallet_creation_flags, const std::string &name,
                  bilingual_str &error, std::vector<bilingual_str> &warnings,
                  WalletCreationStatus &status) = 0;
 
     //! Register handler for init messages.
     using InitMessageFn = std::function<void(const std::string &message)>;
     virtual std::unique_ptr<Handler> handleInitMessage(InitMessageFn fn) = 0;
 
     //! Register handler for message box messages.
     using MessageBoxFn =
         std::function<bool(const bilingual_str &message,
                            const std::string &caption, unsigned int style)>;
     virtual std::unique_ptr<Handler> handleMessageBox(MessageBoxFn fn) = 0;
 
     //! Register handler for question messages.
     using QuestionFn =
         std::function<bool(const bilingual_str &message,
                            const std::string &non_interactive_message,
                            const std::string &caption, unsigned int style)>;
     virtual std::unique_ptr<Handler> handleQuestion(QuestionFn fn) = 0;
 
     //! Register handler for progress messages.
     using ShowProgressFn = std::function<void(
         const std::string &title, int progress, bool resume_possible)>;
     virtual std::unique_ptr<Handler> handleShowProgress(ShowProgressFn fn) = 0;
 
     //! Register handler for load wallet messages.
     using LoadWalletFn = std::function<void(std::unique_ptr<Wallet> wallet)>;
     virtual std::unique_ptr<Handler> handleLoadWallet(LoadWalletFn fn) = 0;
 
     //! Register handler for number of connections changed messages.
     using NotifyNumConnectionsChangedFn =
         std::function<void(int new_num_connections)>;
     virtual std::unique_ptr<Handler>
     handleNotifyNumConnectionsChanged(NotifyNumConnectionsChangedFn fn) = 0;
 
     //! Register handler for network active messages.
     using NotifyNetworkActiveChangedFn =
         std::function<void(bool network_active)>;
     virtual std::unique_ptr<Handler>
     handleNotifyNetworkActiveChanged(NotifyNetworkActiveChangedFn fn) = 0;
 
     //! Register handler for notify alert messages.
     using NotifyAlertChangedFn = std::function<void()>;
     virtual std::unique_ptr<Handler>
     handleNotifyAlertChanged(NotifyAlertChangedFn fn) = 0;
 
     //! Register handler for ban list messages.
     using BannedListChangedFn = std::function<void()>;
     virtual std::unique_ptr<Handler>
     handleBannedListChanged(BannedListChangedFn fn) = 0;
 
     //! Register handler for block tip messages.
-    using NotifyBlockTipFn = std::function<void(
-        SynchronizationState, const BlockHash &block_hash, int height,
-        int64_t block_time, double verification_progress)>;
+    using NotifyBlockTipFn =
+        std::function<void(SynchronizationState, interfaces::BlockTip tip,
+                           double verification_progress)>;
     virtual std::unique_ptr<Handler>
     handleNotifyBlockTip(NotifyBlockTipFn fn) = 0;
 
     //! Register handler for header tip messages.
-    using NotifyHeaderTipFn = std::function<void(
-        SynchronizationState, const BlockHash &block_hash, int height,
-        int64_t block_time, double verification_progress)>;
+    using NotifyHeaderTipFn =
+        std::function<void(SynchronizationState, interfaces::BlockTip tip,
+                           double verification_progress)>;
     virtual std::unique_ptr<Handler>
     handleNotifyHeaderTip(NotifyHeaderTipFn fn) = 0;
 
     //! Get and set internal node context. Useful for testing, but not
     //! accessible across processes.
     virtual NodeContext *context() { return nullptr; }
     virtual void setContext(NodeContext *context) {}
 };
 
 //! Return implementation of Node interface.
 std::unique_ptr<Node> MakeNode(NodeContext *context = nullptr);
 
+//! Block tip (could be a header or not, depends on the subscribed signal).
+struct BlockTip {
+    int block_height;
+    int64_t block_time;
+    BlockHash block_hash;
+};
+
 } // namespace interfaces
 
 #endif // BITCOIN_INTERFACES_NODE_H
diff --git a/src/qt/clientmodel.cpp b/src/qt/clientmodel.cpp
index cc989163f..933dc13d7 100644
--- a/src/qt/clientmodel.cpp
+++ b/src/qt/clientmodel.cpp
@@ -1,325 +1,323 @@
 // Copyright (c) 2011-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <qt/clientmodel.h>
 
 #include <checkpoints.h>
 #include <clientversion.h>
 #include <config.h>
 #include <interfaces/handler.h>
 #include <interfaces/node.h>
 #include <net.h>
 #include <netbase.h>
 #include <qt/bantablemodel.h>
 #include <qt/guiconstants.h>
 #include <qt/guiutil.h>
 #include <qt/peertablemodel.h>
 #include <util/system.h>
 #include <validation.h>
 
 #include <QDebug>
 #include <QThread>
 #include <QTimer>
 
 #include <cstdint>
 
 static int64_t nLastHeaderTipUpdateNotification = 0;
 static int64_t nLastBlockTipUpdateNotification = 0;
 
 ClientModel::ClientModel(interfaces::Node &node, OptionsModel *_optionsModel,
                          QObject *parent)
     : QObject(parent), m_node(node), optionsModel(_optionsModel),
       peerTableModel(nullptr), banTableModel(nullptr),
       m_thread(new QThread(this)) {
     cachedBestHeaderHeight = -1;
     cachedBestHeaderTime = -1;
     peerTableModel = new PeerTableModel(m_node, this);
     banTableModel = new BanTableModel(m_node, this);
 
     QTimer *timer = new QTimer;
     timer->setInterval(MODEL_UPDATE_DELAY);
     connect(timer, &QTimer::timeout, [this] {
         // no locking required at this point
         // the following calls will acquire the required lock
         Q_EMIT mempoolSizeChanged(m_node.getMempoolSize(),
                                   m_node.getMempoolDynamicUsage());
         Q_EMIT bytesChanged(m_node.getTotalBytesRecv(),
                             m_node.getTotalBytesSent());
     });
     connect(m_thread, &QThread::finished, timer, &QObject::deleteLater);
     connect(m_thread, &QThread::started, [timer] { timer->start(); });
     // move timer to thread so that polling doesn't disturb main event loop
     timer->moveToThread(m_thread);
     m_thread->start();
 
     subscribeToCoreSignals();
 }
 
 ClientModel::~ClientModel() {
     unsubscribeFromCoreSignals();
 
     m_thread->quit();
     m_thread->wait();
 }
 
 int ClientModel::getNumConnections(NumConnections flags) const {
     CConnman::NumConnections connections = CConnman::CONNECTIONS_NONE;
 
     if (flags == CONNECTIONS_IN) {
         connections = CConnman::CONNECTIONS_IN;
     } else if (flags == CONNECTIONS_OUT) {
         connections = CConnman::CONNECTIONS_OUT;
     } else if (flags == CONNECTIONS_ALL) {
         connections = CConnman::CONNECTIONS_ALL;
     }
 
     return m_node.getNodeCount(connections);
 }
 
 int ClientModel::getHeaderTipHeight() const {
     if (cachedBestHeaderHeight == -1) {
         // make sure we initially populate the cache via a cs_main lock
         // otherwise we need to wait for a tip update
         int height;
         int64_t blockTime;
         if (m_node.getHeaderTip(height, blockTime)) {
             cachedBestHeaderHeight = height;
             cachedBestHeaderTime = blockTime;
         }
     }
     return cachedBestHeaderHeight;
 }
 
 int64_t ClientModel::getHeaderTipTime() const {
     if (cachedBestHeaderTime == -1) {
         int height;
         int64_t blockTime;
         if (m_node.getHeaderTip(height, blockTime)) {
             cachedBestHeaderHeight = height;
             cachedBestHeaderTime = blockTime;
         }
     }
     return cachedBestHeaderTime;
 }
 
 int ClientModel::getNumBlocks() const {
     if (m_cached_num_blocks == -1) {
         m_cached_num_blocks = m_node.getNumBlocks();
     }
     return m_cached_num_blocks;
 }
 
 BlockHash ClientModel::getBestBlockHash() {
     BlockHash tip{WITH_LOCK(m_cached_tip_mutex, return m_cached_tip_blocks)};
 
     if (!tip.IsNull()) {
         return tip;
     }
 
     // Lock order must be: first `cs_main`, then `m_cached_tip_mutex`.
     // The following will lock `cs_main` (and release it), so we must not
     // own `m_cached_tip_mutex` here.
     tip = m_node.getBestBlockHash();
 
     LOCK(m_cached_tip_mutex);
     // We checked that `m_cached_tip_blocks` is not null above, but then we
     // released the mutex `m_cached_tip_mutex`, so it could have changed in the
     // meantime. Thus, check again.
     if (m_cached_tip_blocks.IsNull()) {
         m_cached_tip_blocks = tip;
     }
     return m_cached_tip_blocks;
 }
 
 void ClientModel::updateNumConnections(int numConnections) {
     Q_EMIT numConnectionsChanged(numConnections);
 }
 
 void ClientModel::updateNetworkActive(bool networkActive) {
     Q_EMIT networkActiveChanged(networkActive);
 }
 
 void ClientModel::updateAlert() {
     Q_EMIT alertsChanged(getStatusBarWarnings());
 }
 
 enum BlockSource ClientModel::getBlockSource() const {
     if (m_node.getReindex()) {
         return BlockSource::REINDEX;
     } else if (m_node.getImporting()) {
         return BlockSource::DISK;
     } else if (getNumConnections() > 0) {
         return BlockSource::NETWORK;
     }
 
     return BlockSource::NONE;
 }
 
 QString ClientModel::getStatusBarWarnings() const {
     return QString::fromStdString(m_node.getWarnings());
 }
 
 OptionsModel *ClientModel::getOptionsModel() {
     return optionsModel;
 }
 
 PeerTableModel *ClientModel::getPeerTableModel() {
     return peerTableModel;
 }
 
 BanTableModel *ClientModel::getBanTableModel() {
     return banTableModel;
 }
 
 QString ClientModel::formatFullVersion() const {
     return QString::fromStdString(FormatFullVersion());
 }
 
 QString ClientModel::formatSubVersion() const {
     return QString::fromStdString(userAgent(GetConfig()));
 }
 
 bool ClientModel::isReleaseVersion() const {
     return CLIENT_VERSION_IS_RELEASE;
 }
 
 QString ClientModel::formatClientStartupTime() const {
     return QDateTime::fromTime_t(GetStartupTime()).toString();
 }
 
 QString ClientModel::dataDir() const {
     return GUIUtil::boostPathToQString(GetDataDir());
 }
 
 QString ClientModel::blocksDir() const {
     return GUIUtil::boostPathToQString(GetBlocksDir());
 }
 
 void ClientModel::updateBanlist() {
     banTableModel->refresh();
 }
 
 // Handlers for core signals
 static void ShowProgress(ClientModel *clientmodel, const std::string &title,
                          int nProgress) {
     // emits signal "showProgress"
     bool invoked = QMetaObject::invokeMethod(
         clientmodel, "showProgress", Qt::QueuedConnection,
         Q_ARG(QString, QString::fromStdString(title)), Q_ARG(int, nProgress));
     assert(invoked);
 }
 
 static void NotifyNumConnectionsChanged(ClientModel *clientmodel,
                                         int newNumConnections) {
     // Too noisy: qDebug() << "NotifyNumConnectionsChanged: " +
     // QString::number(newNumConnections);
     bool invoked = QMetaObject::invokeMethod(
         clientmodel, "updateNumConnections", Qt::QueuedConnection,
         Q_ARG(int, newNumConnections));
     assert(invoked);
 }
 
 static void NotifyNetworkActiveChanged(ClientModel *clientmodel,
                                        bool networkActive) {
     bool invoked = QMetaObject::invokeMethod(clientmodel, "updateNetworkActive",
                                              Qt::QueuedConnection,
                                              Q_ARG(bool, networkActive));
     assert(invoked);
 }
 
 static void NotifyAlertChanged(ClientModel *clientmodel) {
     qDebug() << "NotifyAlertChanged";
     bool invoked = QMetaObject::invokeMethod(clientmodel, "updateAlert",
                                              Qt::QueuedConnection);
     assert(invoked);
 }
 
 static void BannedListChanged(ClientModel *clientmodel) {
     qDebug() << QString("%1: Requesting update for peer banlist").arg(__func__);
     bool invoked = QMetaObject::invokeMethod(clientmodel, "updateBanlist",
                                              Qt::QueuedConnection);
     assert(invoked);
 }
 
 static void BlockTipChanged(ClientModel *clientmodel,
                             SynchronizationState sync_state,
-                            const BlockHash block_hash, int height,
-                            int64_t blockTime, double verificationProgress,
-                            bool fHeader) {
+                            interfaces::BlockTip tip,
+                            double verificationProgress, bool fHeader) {
     if (fHeader) {
         // cache best headers time and height to reduce future cs_main locks
-        clientmodel->cachedBestHeaderHeight = height;
-        clientmodel->cachedBestHeaderTime = blockTime;
+        clientmodel->cachedBestHeaderHeight = tip.block_height;
+        clientmodel->cachedBestHeaderTime = tip.block_time;
     } else {
-        clientmodel->m_cached_num_blocks = height;
+        clientmodel->m_cached_num_blocks = tip.block_height;
         WITH_LOCK(clientmodel->m_cached_tip_mutex,
-                  clientmodel->m_cached_tip_blocks = block_hash;);
+                  clientmodel->m_cached_tip_blocks = tip.block_hash;);
     }
 
     // Throttle GUI notifications about (a) blocks during initial sync, and (b)
     // both blocks and headers during reindex.
     const bool throttle =
         (sync_state != SynchronizationState::POST_INIT && !fHeader) ||
         sync_state == SynchronizationState::INIT_REINDEX;
     const int64_t now = throttle ? GetTimeMillis() : 0;
     int64_t &nLastUpdateNotification = fHeader
                                            ? nLastHeaderTipUpdateNotification
                                            : nLastBlockTipUpdateNotification;
     if (throttle && now < nLastUpdateNotification + MODEL_UPDATE_DELAY) {
         return;
     }
 
     bool invoked = QMetaObject::invokeMethod(
         clientmodel, "numBlocksChanged", Qt::QueuedConnection,
-        Q_ARG(int, height), Q_ARG(QDateTime, QDateTime::fromTime_t(blockTime)),
+        Q_ARG(int, tip.block_height),
+        Q_ARG(QDateTime, QDateTime::fromTime_t(tip.block_time)),
         Q_ARG(double, verificationProgress), Q_ARG(bool, fHeader),
         Q_ARG(SynchronizationState, sync_state));
     assert(invoked);
     nLastUpdateNotification = now;
 }
 
 void ClientModel::subscribeToCoreSignals() {
     // Connect signals to client
     m_handler_show_progress = m_node.handleShowProgress(std::bind(
         ShowProgress, this, std::placeholders::_1, std::placeholders::_2));
     m_handler_notify_num_connections_changed =
         m_node.handleNotifyNumConnectionsChanged(std::bind(
             NotifyNumConnectionsChanged, this, std::placeholders::_1));
     m_handler_notify_network_active_changed =
         m_node.handleNotifyNetworkActiveChanged(
             std::bind(NotifyNetworkActiveChanged, this, std::placeholders::_1));
     m_handler_notify_alert_changed =
         m_node.handleNotifyAlertChanged(std::bind(NotifyAlertChanged, this));
     m_handler_banned_list_changed =
         m_node.handleBannedListChanged(std::bind(BannedListChanged, this));
     m_handler_notify_block_tip = m_node.handleNotifyBlockTip(
         std::bind(BlockTipChanged, this, std::placeholders::_1,
-                  std::placeholders::_2, std::placeholders::_3,
-                  std::placeholders::_4, std::placeholders::_5, false));
+                  std::placeholders::_2, std::placeholders::_3, false));
     m_handler_notify_header_tip = m_node.handleNotifyHeaderTip(
         std::bind(BlockTipChanged, this, std::placeholders::_1,
-                  std::placeholders::_2, std::placeholders::_3,
-                  std::placeholders::_4, std::placeholders::_5, true));
+                  std::placeholders::_2, std::placeholders::_3, true));
 }
 
 void ClientModel::unsubscribeFromCoreSignals() {
     // Disconnect signals from client
     m_handler_show_progress->disconnect();
     m_handler_notify_num_connections_changed->disconnect();
     m_handler_notify_network_active_changed->disconnect();
     m_handler_notify_alert_changed->disconnect();
     m_handler_banned_list_changed->disconnect();
     m_handler_notify_block_tip->disconnect();
     m_handler_notify_header_tip->disconnect();
 }
 
 bool ClientModel::getProxyInfo(std::string &ip_port) const {
     proxyType ipv4, ipv6;
     if (m_node.getProxy((Network)1, ipv4) &&
         m_node.getProxy((Network)2, ipv6)) {
         ip_port = ipv4.proxy.ToStringIPPort();
         return true;
     }
     return false;
 }
diff --git a/src/qt/clientmodel.h b/src/qt/clientmodel.h
index 370f1cd71..bfbdc3c3f 100644
--- a/src/qt/clientmodel.h
+++ b/src/qt/clientmodel.h
@@ -1,130 +1,130 @@
 // Copyright (c) 2011-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_QT_CLIENTMODEL_H
 #define BITCOIN_QT_CLIENTMODEL_H
 
 #include <QDateTime>
 #include <QObject>
 
 #include <atomic>
 #include <memory>
 #include <primitives/blockhash.h>
 #include <sync.h>
 
 class BanTableModel;
 class CBlockIndex;
 class OptionsModel;
 class PeerTableModel;
 
 class CBlockIndex;
 enum class SynchronizationState;
 
 namespace interfaces {
 class Handler;
 class Node;
 } // namespace interfaces
 
 QT_BEGIN_NAMESPACE
 class QTimer;
 QT_END_NAMESPACE
 
 enum class BlockSource { NONE, REINDEX, DISK, NETWORK };
 
 /** Model for Bitcoin network client. */
 class ClientModel : public QObject {
     Q_OBJECT
 
 public:
     enum NumConnections {
         CONNECTIONS_NONE = 0,
         CONNECTIONS_IN = (1U << 0),
         CONNECTIONS_OUT = (1U << 1),
         CONNECTIONS_ALL = (CONNECTIONS_IN | CONNECTIONS_OUT),
     };
 
     explicit ClientModel(interfaces::Node &node, OptionsModel *optionsModel,
                          QObject *parent = nullptr);
     ~ClientModel();
 
     interfaces::Node &node() const { return m_node; }
     OptionsModel *getOptionsModel();
     PeerTableModel *getPeerTableModel();
     BanTableModel *getBanTableModel();
 
     //! Return number of connections, default is in- and outbound (total)
     int getNumConnections(NumConnections flags = CONNECTIONS_ALL) const;
     int getNumBlocks() const;
     BlockHash getBestBlockHash();
     int getHeaderTipHeight() const;
     int64_t getHeaderTipTime() const;
 
     //! Returns enum BlockSource of the current importing/syncing state
     enum BlockSource getBlockSource() const;
     //! Return warnings to be displayed in status bar
     QString getStatusBarWarnings() const;
 
     QString formatFullVersion() const;
     QString formatSubVersion() const;
     bool isReleaseVersion() const;
     QString formatClientStartupTime() const;
     QString dataDir() const;
     QString blocksDir() const;
 
     bool getProxyInfo(std::string &ip_port) const;
 
-    // caches for the best header, number of blocks
+    // caches for the best header: hash, number of blocks and block time
     mutable std::atomic<int> cachedBestHeaderHeight;
     mutable std::atomic<int64_t> cachedBestHeaderTime;
     mutable std::atomic<int> m_cached_num_blocks{-1};
 
     Mutex m_cached_tip_mutex;
     BlockHash m_cached_tip_blocks GUARDED_BY(m_cached_tip_mutex){};
 
 private:
     interfaces::Node &m_node;
     std::unique_ptr<interfaces::Handler> m_handler_show_progress;
     std::unique_ptr<interfaces::Handler>
         m_handler_notify_num_connections_changed;
     std::unique_ptr<interfaces::Handler>
         m_handler_notify_network_active_changed;
     std::unique_ptr<interfaces::Handler> m_handler_notify_alert_changed;
     std::unique_ptr<interfaces::Handler> m_handler_banned_list_changed;
     std::unique_ptr<interfaces::Handler> m_handler_notify_block_tip;
     std::unique_ptr<interfaces::Handler> m_handler_notify_header_tip;
     OptionsModel *optionsModel;
     PeerTableModel *peerTableModel;
     BanTableModel *banTableModel;
 
     //! A thread to interact with m_node asynchronously
     QThread *const m_thread;
 
     void subscribeToCoreSignals();
     void unsubscribeFromCoreSignals();
 
 Q_SIGNALS:
     void numConnectionsChanged(int count);
     void numBlocksChanged(int count, const QDateTime &blockDate,
                           double nVerificationProgress, bool header,
                           SynchronizationState sync_state);
     void mempoolSizeChanged(long count, size_t mempoolSizeInBytes);
     void networkActiveChanged(bool networkActive);
     void alertsChanged(const QString &warnings);
     void bytesChanged(quint64 totalBytesIn, quint64 totalBytesOut);
 
     //! Fired when a message should be reported to the user
     void message(const QString &title, const QString &message,
                  unsigned int style);
 
     // Show progress dialog e.g. for verifychain
     void showProgress(const QString &title, int nProgress);
 
 public Q_SLOTS:
     void updateNumConnections(int numConnections);
     void updateNetworkActive(bool networkActive);
     void updateAlert();
     void updateBanlist();
 };
 
 #endif // BITCOIN_QT_CLIENTMODEL_H