Extend the test

polkadot/runtime/parachains/src/paras/tests.rs

@@ -576,7 +576,12 @@ fn upgrade_strategy_apply_at_expected_block_works() {
 		submit_super_majority_pvf_votes(&new_code, EXPECTED_SESSION, true);
 		assert!(FutureCodeUpgradesAt::<Test>::get().iter().any(|(id, _)| *id == para_id));
 
-		run_to_block(expected_at + 1, None);
+		// Going to the expected block triggers the upgrade directly.
+		run_to_block(expected_at, None);
+
+		// Reporting a head doesn't change anything.
+		Paras::note_new_head(para_id, Default::default(), expected_at - 1);
+
 		assert_eq!(Paras::past_code_meta(&para_id).most_recent_change(), Some(expected_at));
 		assert_eq!(PastCodeHash::<Test>::get(&(para_id, expected_at)), Some(original_code.hash()));
 		assert!(FutureCodeUpgrades::<Test>::get(&para_id).is_none());