Had a 5-lap race with compulsory pitstop today. I forgot to pit, and when the leader finished, I saw a message "30 seconds penalty for late pit-stop". I didn't pit on last lap and was DQed. But the message "30 seconds penalty for late pitstop" remained on screen.

I think, when you are dq, the penalty should be erased as irrelevant. Even though it is not a bug, it looks like 1.