Will iOS 7 remove my ability to use the H2O Carrier?

[modman2]

I want to update my iPhone 4 to the 7 GM but i'm worried that the phone might lock me out without a proper sim card from like AT&T.

EDIT: I went ahead and updated. Everything went fine and as expected!

 

[bbfc]

I want to update my iPhone 4 to the 7 GM but i'm worried that the phone might lock me out without a proper sim card from like AT&T.

Was your phone 'officially' unlocked from AT&T?

 

[dictoresno]

As the case with all gsm phones, once unlocked by official unlock code.....always unlocked. OS's, firmware etc...cant relock a phone. Unless you did a jailbreak tweak or similar unlocking method, then it probably will relock it.

 

[modman2]

I don't think it's ever been jailbroken so I guess I can assume it should be unlocked

 

[Gregintosh]

Lets ask it another way. Did you use any sort of hacking or trickery to get your sim card working? If yes, then you may lose the ability to use it. If all you did was get a phone and pop it in and it worked just fine (without any jailbreaks or tricks) then it's fine.