If I upgrade to 4.0 from 3.1.3, will I lose my unlock?

[OrlandoTragic]

I have a 3GS with new bootrom running 3.1.3..

I'm selling the phone, and the buyer wants 4.0, doesn't care if its not jailbroken.

Can I upgrade to 4.0, or will I lose the unlock?

 

[nszzya]

I have a 3GS with new bootrom running 3.1.3..

I'm selling the phone, and the buyer wants 4.0, doesn't care if its not jailbroken.

Can I upgrade to 4.0, or will I lose the unlock?

You will lose the unlock.

 

[Blazing angel]

I have a 3GS with new bootrom running 3.1.3..

I'm selling the phone, and the buyer wants 4.0, doesn't care if its not jailbroken.

Can I upgrade to 4.0, or will I lose the unlock?

NO, you wont. A new ultrasnow is out, from repo666.ultrasn0w.com

it unlocks every baseband, including 4.0's 0.5.13

 

[jlmitnick]

NO, you wont. A new ultrasnow is out, from repo666.ultrasn0w.com

it unlocks every baseband, including 4.0's 0.5.13

While it's true that the new ultrasn0w unlocks every baseband, if he upgrades to stock 4.0 and is not jailbroken, he'll have no way to run ultrasn0w and thus lose the unlock.

 

[ryanbates]

NO, you wont. A new ultrasnow is out, from repo666.ultrasn0w.com

it unlocks every baseband, including 4.0's 0.5.13

True but he states that he has an iPhone 3GS with the new bootrom. Currently the only jailbreak available for the new bootrom is the Spriit Jailbreak and it is not compatible with iOS4. Pwnage and Redsn0w only work with the old bootrom.

To answer you question duelingdragons, you will have to downgrade the iPhone to 3.1.3 to unlock it. There is currently no way to jailbreak iOS4 with the new bootrom.