I like the indefinite editing time-
every few months I liked to go back and clean up { take out personal info or chit chat or ?}

Perhaps if a post was made in the heat of the moment and someone has a change of heart or cools off at a later date - self editing is a nice option to have.

If a "bad" post is found or needs to be reported -
It can be copied or quoted correct?
To "save" it in the unchanged version.

I think the option for posters to self edit should have a longer time frame.