I find this very interesting. Wish I had looked here before I called T-Mobile. I spend two hours on the phone with T-Mobile this afternoon and they never mentioned possible outages. I am not using a T-Mobile supported router (Netgear) but it was working fine for a month, then today… They did ask me to go to a T-Mobile store to see if I can connect to the UMA server from the store router. If I can then the issue is my home router…