Re: make deletion routine
It's a pain in the ass, though, to have chat ephemeral. My company set it to 30 days after having no retention set. By that point, everyone had stopped using email and were chatting preliminary project design decisions, preliminary functional agreements etc. All lost, and chaos and arguments ensued for some months. Even on a personal level, having to reask who someone is (it's a large company) every time they infrequently ping you is painful.
"Only personal chats were lost, it's claimed, not chats conducted as part of a Teams meeting or Teams channel, and not any files uploaded to personal chat threads."
This is what MS say, but the meeting chats disapper too. Only chats in a channel are safe, but the channels are broken once you have more than six. Files you upload are still there, somewhere, but the link to them is removed, so finding them can be challenging...