diff --git a/test/functional/test_framework/util.py b/test/functional/test_framework/util.py
--- a/test/functional/test_framework/util.py
+++ b/test/functional/test_framework/util.py
@@ -330,6 +330,10 @@
         f.write("rpcport=" + str(rpc_port(n)) + "\n")
         f.write("listenonion=0\n")
         f.write("usecashaddr=1\n")
+        # Activate 'great wall' protocol upgrade in the past by default. This
+        # lets us discover incompatiblities before activation. Tests can
+        # explicitly override this using extra_args. Timestamp is 01.01.2019.
+        f.write("greatwallactivationtime=1546300800\n")
     return datadir