Internet service and VoIP

I have been following this thread for some time as my VOIP service with VOIP.MS (and all other VOIP lines) suddenly stopped working late April 2024 (it was working for over a year). 

A couple of days ago, I decided to call T-Mobile customer support to see what my experience would be like.  I convinced them to escalate my issue to the Business support team since this is more of a business type of issue. I was offered Ooma, which is apparently a T-Mobile service, but I declined since I use my own PBXs and other 3rd party VOIP services. What I got them to admit is that a recent upgrade to the KVD21 (also to the new TMO G4AR gateway) prevents T-Mobile Home Internet end users from using 3rd party VOIP services. The reasoning behind this could not be explained even though I tried to extract this information, it was apparently at a "higher pay grade" than the technician I was speaking to. Long story shorter… the solution is to use my Inseego M2000 portable hotspot for VOIP.

We can hope is that if enough of us protest this feature change (“its not a bug, it’s a feature”), the engineers will revert what ever they did to block use of VOIP on T-Mobiles Internet service in a future release.