diff --git a/tests/core_tests/chaingen_main.cpp b/tests/core_tests/chaingen_main.cpp
index 102b3116..8c3dc903 100644
--- a/tests/core_tests/chaingen_main.cpp
+++ b/tests/core_tests/chaingen_main.cpp
@@ -747,6 +747,11 @@ int main(int argc, char* argv[])
     MARK_TEST_AS_POSTPONED(gen_wallet_spending_coinstake_after_minting);
     MARK_TEST_AS_POSTPONED(gen_wallet_fake_outs_while_having_too_little_own_outs);
     MARK_TEST_AS_POSTPONED(gen_uint_overflow_1);
+
+    MARK_TEST_AS_POSTPONED(after_hard_fork_1_cumulative_difficulty); // reason: set_pos_to_low_timestamp is not supported anymore
+    MARK_TEST_AS_POSTPONED(before_hard_fork_1_cumulative_difficulty);
+    MARK_TEST_AS_POSTPONED(inthe_middle_hard_fork_1_cumulative_difficulty);
+
     MARK_TEST_AS_POSTPONED(zarcanum_basic_test);
 
 #undef MARK_TEST_AS_POSTPONED
diff --git a/tests/core_tests/hard_fork_1_consensus_test.cpp b/tests/core_tests/hard_fork_1_consensus_test.cpp
index dd672019..485f32c3 100644
--- a/tests/core_tests/hard_fork_1_consensus_test.cpp
+++ b/tests/core_tests/hard_fork_1_consensus_test.cpp
@@ -42,7 +42,8 @@ bool hard_fork_1_cumulative_difficulty_base::generate(std::vector<test_event_ent
 
     last_block = next_blk_pow;
   }
-
+  
+  // generator.set_pos_to_low_timestamp(true); <-- this is not supported anymore -- sowle
   last_block = blk_0r; 
   for (size_t i = 0; i != 20; i++)
   {