I have an iPhone 5 and have a weird issue. I have AT&T and have a great signal everywhere I go and don't have an issue except when I'm at work at one area. We have a warehouse that is a metal pole barn and you don't get a cell signal in there. We have wifi set up in the warehouse and whenever I go to the warehouse and then leave I never have a data connection and when I do it is only edge. We have other areas of work that have wifi and when I leave those areas the signal is fine because I never lose the data or cell signal. Only in the warehouse. If I restart the phone it corrects the problem. I have even tried turning off the data connection in the settings and when I leave and turn it back on it goes to edge anyway. This is really annoying and if anyone has any ideas that would be a great help.
Thanks,
Kevin
What is your 4G signal like outside the warehouse?
My iPhone 5 behaves in a similar manner. However I'm thinking/finding that iOS 6.x greatly favors a the slower network with better signal than the faster network with even 2-3 bars. What you describe happens at my work as well and some times home in certain areas of the house. It will fall to EDGE and stay there, not very good 4G signal inside at work. Eventually it will jump back up. If I switch to air plane mode it will go back to 4G every time if it's sitting on EDGE.
Two weeks ago at a super bowl party two of my friends and I have iPhone 5's. They live in an LTE area also with great 4G signal. In side their apartment all 3 of our phones would get 1-3 bars of LTE and then fall to 4G with full bars. The phones would remain there for awhile and sometimes go back to LTE and sometimes not. I actually watched all 3 of them do this and they were all doing at the same times roughly as well. On another note; another friend's GS3 couldn't get LTE signal at all in the apartment.
So I think you might be seeing normal behavior for iOS 6. I was ready to exchange mine as well since I saw it dropping to EDGE all the time inside work but then when I leave it is reluctant to jump back to 4G.
Really your only options are to restore as new. If that doesn't help you could get it exchanged at Apple. But you may see the same type of behavior. Does anyone else at your work have this issue with an iPhone 5?