I have an unlocked iPhone 3GS that I’m currently using with provider PureTalk.
It is currently using iOS version 4.0. It is jailbroken and unlocked.
I want to update the phone to version 6.1.6 but I am afraid of losing the unlock (don’t really care about the jailbreak) and I fear it would be make the phone unusable due the fact that I have a PureTalk SIM card installed and not a AT&T. I do have a non-working AT&T sim card I can swap out but not sure if that will help or affect things.
Can someone please help me?