> Okay, so, what will this link do?
> https://twitter.com/POTUS/status/786254141182074880
> Will it go to a page that says deleted? Is that what "no tweets on the timeline" means? Will each tweet link redirect to the copy?
I think the only important part of the URL is the ID number at the end. So, no matter what the username is changed to, as long as you have that unique numeric ID, it will go to the correct place. You can check this by changing the "POTUS" string to anything else you like, and sending your browser to that modified URL:
https://twitter.com/POTUS44/status/786254141182074880
Presently, the above URL redirects to the POTUS one you posted, but that just goes to show that the numeric ID is the important identifier.