Downgraded an iPad2 from 6.1.2 to 5.1.1 and lost my unlock. HELP!
I'm not sure whether this is in the right place but the iPad forum seems to be closed. My apology if it's misposted. Please direct me to the proper place.
I recently purchased an iPad 2 at 6.1.2. Fortunately, the previous owner saved the hashes for 4.3.5, 5.1.1, 6.1.2 et al. in between. Using the procedure on the iClarified site, I was able to successfully downgrade from 6.1.2 to 5.1.1 using Redsn0w and then Jailbreak with Absinthe. So far so good.
I would like to switch to T-Mobile but it appears that the iPad2 managed to get relocked to AT&T. Yes, I know that they are all supposed to be unlocked. When I put the T-Mobile sim in the device, it still indicates AT&T 12.0 as the carrier after a reboot (T-Mobile guy said it sometimes gets relocked during a restore in iTunes). I called AT&T to get it re-unlocked and they said that they reissued the network unlock and that I should backup and "restore" my iPad. Option-clicking the "restore" pulldown in iTunes tells me that it will erase and reinstall 5.1.1. Since I'll be using a locally stored IPSW (from iClarified) and Apple isn't signing 5.1.1 anymore how will it know to unlock the iPad? Furthermore, it takes an hour or 2 (or 3) to reinstall the OS, sync, Jailbreak, add all the Cydia apps etc. so I don't want to do this capriciously. Is this correct? Will the IMEI unlock be restored if I go through this entire process again? I'm now completely confused!
I hope you can clear up this confusion. Thanks in advance