Earlier quoted context omitted.
Does it still show bars in SOS mode? Or is SOS just “I dunno can’t see no cell towers but maybe it’d work?” I wonder if the MVNOs that piggyback on AT&T are showing down also. If not, it’s some AT&T service authorization system that exploded.
On the latest iPhones, SOS mode is the emergency fallback to satellite service. It's really meant to be used in situations where you're well outside of any sort of service area but you have a clear, unobstructed view of the sky. Your iPhone will instruct you on where to point and help you track an emergency satellite that is manned by live humans who will take your emergency request and relay it to the proper people.…
If there is no cell service then it's SOS with a little picture of a satellite next to it.