AFAIK, it’s not tied to trust level. The amount of time users are able to edit posts is determined by the forum’s Discourse (the software this forum uses) configuration. I don’t know what it’s set to here, but I believe out of the box it’s two months?
So after two months, posts aren’t editable by the poster unless they are a wiki post. Someone with access to the forum’s settings (i.e., COG staff) could set posts to remain editable forever, but that would be up to them to do.
Obviously, do what’s within your comfort level, but if it makes you feel better, unauthorized first post editing is exceptionally rare (to my knowledge) and not accepted.
Every edit is recorded by the forum, so as awful as malicious editing is, it’s also terribly ineffective; it takes but a second to undo and it’s obvious who did it.
If you click on the pencil icon on an edited post, you can quickly access the raw code for the post. Restoration is as simple as a copy-paste.
