Unmark sub requests that are AI players

A player marks themselves for substitution. Let’s say they leave.
At this point, the players can pause the game while a sub is being advertised.
However, if the game resumes past a few turns; it is obvious now that a player is not subbing in.

I was wondering if the Game Master can clear the sub request, or something like after the AI player has played X turns, the sub request is auto removed.

I am a GM of games, or am in games where we have AI in sub request mode, but we have accepted the AI is now playing.