I have an iPhone 4S running iOS 5.1.1 on AT&T in the U.S. AT&T has approved an unlock request I submitted, so I have to connect my iPhone to iTunes, back up, restore to factory settings, and then restore my backup onto the phoneafter doing this my iPhone will re-activate with AT&T and will receive a carrier-sanctioned permanent unlock. I've done with this an iPhone 4 recently and it's a fairly straightforward process. Since I last did this, though, iOS 6 has come out. I'm personally not interested in upgrading my iPhone 4S to iOS 6 for the time being. I have never jailbroken my phone, but I feel that if I am currently running iOS 5.1.1 I should be able to restore to it too. I know I can do this via the iPhone itself in the Settings app, but the official iPhone unlock instructions provided by both Apple and AT&T say it must be done on an iPhone. Is it possible to restore an iPhone to factory settings in iTunes without updating past the current version of iOS on the phone? If not, is it possible to receive a carrier-provided unlock if one restores from the iPhone itself? Thanks for any help!