When do Edits in an old message trigger an update to users / Message Order

[BCHK (Bcguy)]

@gerhard

If I’m not mistaken, editing the last post in the topic will bring it to the top of the list. All other edits won’t.

But will either scenario - editing last post, or other edit - result in that message being resent to the people who have participated in that thread?

Or - are only entirely “new” posts broadcast to the thread participants?