I am close to the end of a trial of a T-Mo MVNO. It is clear that, at least in my area of the US, T-Mo is having issues with capacity and/or config. What happens to me is that hotspot mode on my 4G phone slowly dies, then the phone's access to data dies, then no telephony at all is possible.
The solution from the MVNO is to switch to another APN and sometimes restart the phone, so in order to use that SIM i need at least two and preferably three nearly identical APN's to switch among as time passes, the expiration being variable. The story being told to me is that T-Mo is reconfiguring towers for 5G. It seems to me that 5G might demand more out of the existing hardware and some gros scrimmage just realised that when he put off some engineers pointing this out he screwed up. Not himself of course, but the customers and shareholders.
I stuck with 3G during the onset of 4G and can't see any reason why not to do the same with this transition, so it's amusing that the carriers themselves are now suggesting this course.
Biting the hand that feeds IT
