diff --git a/src/init.cpp b/src/init.cpp
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -319,7 +319,7 @@
     std::vector<std::string> hidden_args = {
         "-rpcssl", "-benchmark", "-h", "-help", "-socks", "-tor", "-debugnet",
         "-whitelistalwaysrelay", "-blockminsize", "-dbcrashratio",
-        "-forcecompactdb", "-usehd", "-parkdeepreorg",
+        "-forcecompactdb", "-usehd", "-parkdeepreorg", "-automaticunparking",
         "-replayprotectionactivationtime",
         // GUI args. These will be overwritten by SetupUIArgs for the GUI
         "-allowselfsignedrootcertificates", "-choosedatadir", "-lang=<lang>",
diff --git a/src/validation.cpp b/src/validation.cpp
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -2571,7 +2571,7 @@
             // If this is a parked chain, but it has enough PoW, clear the park
             // state.
             bool fParkedChain = pindexTest->nStatus.isOnParkedChain();
-            if (fParkedChain && gArgs.GetBoolArg("-parkdeepreorg", true)) {
+            if (fParkedChain && gArgs.GetBoolArg("-automaticunparking", true)) {
                 const CBlockIndex *pindexTip = chainActive.Tip();
 
                 // During initialization, pindexTip and/or pindexFork may be
@@ -2645,6 +2645,13 @@
                 pindexBestParked = pindexNew;
             }
 
+            LogPrintf("Considered switching to better tip %s but that chain "
+                      "contains a%s%s%s block.\n",
+                      pindexNew->GetBlockHash().ToString(),
+                      fInvalidChain ? "n invalid" : "",
+                      fParkedChain ? " parked" : "",
+                      fMissingData ? " missing-data" : "");
+
             CBlockIndex *pindexFailed = pindexNew;
             // Remove the entire chain from the set.
             while (pindexTest != pindexFailed) {
diff --git a/test/functional/abc-parkedchain.py b/test/functional/abc-parkedchain.py
--- a/test/functional/abc-parkedchain.py
+++ b/test/functional/abc-parkedchain.py
@@ -5,13 +5,14 @@
 """Test the parckblock and unparkblock RPC calls."""
 
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, wait_until
+from test_framework.util import assert_equal, connect_nodes_bi, wait_until
 
 
 class ParkedChainTest(BitcoinTestFramework):
     def set_test_params(self):
         self.num_nodes = 2
-        self.extra_args = [["-noparkdeepreorg"], ["-maxreorgdepth=-1"]]
+        self.extra_args = [["-noparkdeepreorg",
+                            "-noautomaticunparking"], ["-maxreorgdepth=-1"]]
 
     # There should only be one chaintip, which is expected_tip
     def only_valid_tip(self, expected_tip, other_tip_status=None):
@@ -188,6 +189,30 @@
         check_reorg_protection(6, 6)
         check_reorg_protection(100, 100)
 
+        self.log.info("Test that unparking works when -parkdeepreorg=0")
+        # Set up parking node height = fork + 4, node height = fork + 5
+        node.invalidateblock(node.getbestblockhash())
+        parking_node.generate(3)
+        node.generate(5)
+        wait_for_parked_block(node.getbestblockhash())
+        # Restart the parking node without parkdeepreorg.
+        self.restart_node(1, ["-parkdeepreorg=0"])
+        parking_node = self.nodes[1]
+        connect_nodes_bi(node, parking_node)
+        # The other chain should still be marked 'parked'.
+        wait_for_parked_block(node.getbestblockhash())
+        # Three more blocks is not enough to unpark. Even though its PoW is
+        # larger, we are still following the delayed-unparking rules.
+        node.generate(3)
+        wait_for_parked_block(node.getbestblockhash())
+        # Final block pushes over the edge, and should unpark.
+        node.generate(1)
+        wait_until(lambda: parking_node.getbestblockhash() ==
+                   node.getbestblockhash(), timeout=5)
+
+        # Do not append tests after this point without restarting node again.
+        # Parking node is no longer parking.
+
 
 if __name__ == '__main__':
     ParkedChainTest().main()
diff --git a/test/lint/check-doc.py b/test/lint/check-doc.py
--- a/test/lint/check-doc.py
+++ b/test/lint/check-doc.py
@@ -37,6 +37,7 @@
                                        '-debugnet',
                                        '-forcecompactdb',
                                        '-parkdeepreorg',
+                                       '-automaticunparking',
                                        # Remove after May 2020 upgrade
                                        '-phononactivationtime',
                                        '-replayprotectionactivationtime',