It was a T-mobile screwup
Given that T-mobile is now claiming "Apple has addressed the issue within iOS 10" but the fix is actually to install a new carrier update (version 25.2) it sure looks to have been T-mobile's issue...
Given that T-mobile is now claiming "Apple has addressed the issue within iOS 10" but the fix is actually to install a new carrier update (version 25.2) it sure looks to have been T-mobile's issue...