There's a similar post here but I think my situation is slightly different.
I deleted an answer I posted in SO, after realising I've misread the question. So I proceed to edit the deleted post so as to fit the question better, without getting down-voted :P
After about a minute into the edit, the top bar dropped this message: This post has been deleted - no more edits are allowed
I thought the OP was deleted and check it out. It wasn't. So I tried again and the same thing happened.
However I am still able to perform the edit the third time round because I've copy-and-paste-and-post again within 15 seconds.
Is there something about this I do not know? I'm trying to persuade myself this is not a bug.
EDIT:
The "Save Your Edits" button will be disabled after the prompt bar dropped down: