Issue: Minor edits not documented in auctions thread

We noticed in a recent signature auction that minor edits, such as changing a few numbers are not visually documented. Even a mod could not discern an edit having taken place even though the auctioneers themselves saw the edited post prior to and after editing.

In a test post in my own shop thread I realized the following:

I posted a test message, opened the post in a second tab and hit edit post in both tabs.
I actually edited the post in second tab and hit save, then closed the tab.
I hit cancel edit in first tab and refreshed the page. The post did not appear with a "post edited..." message at the bottom.

I tried changing just a couple of characters in an older post after that and the message definitely appeared, so I assume posts are editable as long as they are not yet very old.

This presents a problem in auctions section, because obviously, people would be able to change their non-winning bids into winning ones.

So the question is whether it would be possible to disallow edits in auction section, the same way it's handled in contest section, with the option for auctioneers to edit their first posts in a corresponding auction "graveyard".

In case this is just a bug, perhaps it would be possible to look into this, thank you.