will a unlocked sonim xp3 phone work for t-mobile after january 1 2022

I ended up stopping in at a T-mobile store and asked about this. The supervisor was eventually called out and he determined that my Sonim XP3 would work fine, and that I got these messages because they were just automatically sent out to everyone who didn't have some such-and-such kind of phone or something.

Additionally, the promotion for the free replacement is only available to people paying for a much more expensive plan that I have, so in my case it would have been a very expensive replacement.