There's a checkbox for deleting posts of the users too.
Bluh, I made a typo. I meant I didn't know how deleting their accounts would affect their posts in active threads. I think there are like 1 or 2 threads that are still alive that have AoT players and it would be odd if people were, say, quoting non-existent posts within the thread if they get deleted.
unless what you mean is that when deleting their account you can choose to preserve their posts