diff --git a/test/functional/abc-mempool-coherence-on-activations.py b/test/functional/abc-mempool-coherence-on-activations.py
--- a/test/functional/abc-mempool-coherence-on-activations.py
+++ b/test/functional/abc-mempool-coherence-on-activations.py
@@ -251,8 +251,9 @@
             node.p2p.send_blocks_and_test([block(5200 + i)], node)
 
         # Check we are just before the activation time
-        assert_equal(node.getblockheader(node.getbestblockhash())['mediantime'],
-                     ACTIVATION_TIME - 1)
+        assert_equal(
+            node.getblockchaininfo()['mediantime'],
+            ACTIVATION_TIME - 1)
 
         # We are just before the fork. Pre-fork-only and always-valid chained
         # txns (tx_chain0, tx_chain1) are valid, post-fork-only txns are
@@ -360,8 +361,9 @@
         # Perform the reorg
         node.p2p.send_blocks_and_test(reorg_blocks, node)
         # reorg finishes after the fork
-        assert_equal(node.getblockheader(node.getbestblockhash())['mediantime'],
-                     ACTIVATION_TIME + 2)
+        assert_equal(
+            node.getblockchaininfo()['mediantime'],
+            ACTIVATION_TIME + 2)
         # In old mempool: tx_chain2, tx_post1
         # Recovered from blocks: tx_chain0, tx_chain1, tx_post0
         # Lost from blocks: tx_pre0
diff --git a/test/functional/abc-replay-protection.py b/test/functional/abc-replay-protection.py
--- a/test/functional/abc-replay-protection.py
+++ b/test/functional/abc-replay-protection.py
@@ -215,8 +215,9 @@
         node.p2p.send_blocks_and_test(activation_blocks, node)
 
         # Check we are just before the activation time
-        assert_equal(node.getblockheader(node.getbestblockhash())['mediantime'],
-                     REPLAY_PROTECTION_START_TIME - 1)
+        assert_equal(
+            node.getblockchaininfo()['mediantime'],
+            REPLAY_PROTECTION_START_TIME - 1)
 
         # We are just before the fork, replay protected txns still are rejected
         assert_raises_rpc_error(-26, RPC_INVALID_SIGNATURE_ERROR,
@@ -241,8 +242,9 @@
         node.p2p.send_blocks_and_test([self.tip], node)
 
         # Check we just activated the replay protection
-        assert_equal(node.getblockheader(node.getbestblockhash())['mediantime'],
-                     REPLAY_PROTECTION_START_TIME)
+        assert_equal(
+            node.getblockchaininfo()['mediantime'],
+            REPLAY_PROTECTION_START_TIME)
 
         # Non replay protected transactions are not valid anymore,
         # so they should be removed from the mempool.