iOS 6 Permanent Unlock Trick? (My method)
(This is my first post on this website as I was looking for somewhere I could share this information!)
I think I accidentally found a way to permanently unlock my iPhone 3GS (New Bootrom).
I was running iOS 5.1.1, jailbroken and unlocked on Modem Firmware 5.13.04, and decided to update to iOS 6 to see how good it was. I backed up my data, restored and then update my device until it was eventually up and running iOS 6.0.1. I then restored from the backup, and after that had completed complete the setup on my phone. I thought to myself this was quite strange as before, on 5.1.1 I had to hacktivate my device to get to the home screen. But, I didn't have to for some reason. (Maybe because of the backup?). Once more, I realised I rely on the jailbreak to unlock my phone. But I was suprised as when I looked to see the signal, it showed up with my carrier. Bearing in mind at this point I didn't even launch redsn0w to jailbreak my device, I was unlocked (I think) and therefore did not need to jailbreak!
Steps to do this:
1) Backup an unlocked, Jailbroken copy of your iOS 5.1.1 using iTunes.
2) Restore iPhone using iTunes to iOS 6.0.1
3) When this is complete, restore to the unlocked backup when prompted to in iTunes.
4) You should now be unlocked using a clean version of iOS!
Now I dont know if this will definitely work with all devices, so here are the details for my device:
iPhone 3GS 16GB
Modem Firmware on iOS 5: 5.13.04
Modem Firmware on iOS 6: 5.16.07
Serial Number: 85010******
If your device has similar credentials to mine please try this and report back! Thanks!