I think this question's revisions and timeline should be reviewed.
The timeline I see as a problem is:
- Question asked
- Answer added
- Bounty added to the question
- Answer edited by the same user who created it
- Answer accepted
- Bounty ends
NO bounty is awarded in this case.
I think the edit is clearly a way of adding the solution to the question without creating two answers from the same user. So it is in reality a new questio nthat happens after the bounty has started.
From the help center:
If the bounty was started by the question owner, and the question owner accepts an answer during the bounty period, and the bounty expires without an explicit award – we assume the bounty owner liked the answer they accepted and award it the full bounty amount at the time of bounty expiration.
So why an exception for answer that are created before but still accepted after the bounty has started?