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

Sprint/t-mobile offered to send free 5G capable phones to any subscriber whose phone was believed by them to be incapable of working on the t-mobile network after the end of May 2022.. when the 3G transmitters were turned off… or had Sprint  phones only CDMA capable.  They did in fact send me one free (an Alcatel GoFlip) to replace one of my two phones that they essentially killed.

I'm having a nightmare trying to get them to send the second replacement phone to me. One of the several catches I run into is to get a rep to work with me they have to send a verification text to my phone.. Of course that's the phone that they've disabled.   At this point over 4 hours on phone calls. still no phone.

By the way…. I got one of my phones activated on a t-mobile pre-pay plan that’s only $10 per month.

Unlimited text and voice, and 1GB of data.

To add to the confusion (as one of the owners of a Sprint-obtained Sonim XP3 flip phone):

-----------------the saga continues --------------------------

Today I got an email from t-mobile saying after July 1 when 3G shuts down it would not work, and to click on a link in the email to get a free OnePlus NORD N200 5G phone. On logging onto my account with/through that link I found myself in my account but with no access to any upgrade.

I called t-mobile customer service and first complained that I believed the notice that my phone would stop working after 3G shutdown was incorrect… that in fact it is 4G LTE compatible.

After quite some time she confirmed that.

Then I said, basically, well, if I can get a free upgrade to a 5G phone, let's go ahead and do that. But I want a flip phone. Response was "if you want a flip phone upgrade/trade-in you'll have to pay for it. So I scratched that, and said "Send me the free 5G phone." Well, turns out even that is a shell game.. they switched that from the NORD to a Revvl 5G. I said, OK send that. Then it was "there will be  $35 charge." Huh? When is free $35…. but I said OK, proceed, and was prepared to let them put a $35 charge or give them a credit card. Well, at this point I've been on hold with the rep for about 30 minutes with her saying things like "please hold while I work on this."  She has twice sent me temporary PINs.

Seems like a complete FUBAR with their "free upgrades" … at least in my experience with this one t-mobile account… and even worse with my two legacy Sprint accounts.  Finally I just told her to forget it… She said take my old phone into a t-mobile store and do a trade in there. We'll see. Don't hold your breath.