Baseband Update?

[CorMeister]

I have an iPhone4 (GSM) on iOS 4.1 with baseband 02.10.04, jailbroken with greenpois0n.

My question is, if I update my iPhone4 to iOS 4.3.1, will my baseband be updated? If so, is there a way to update to iOS 4.3.1 without updating my baseband? I understand 02.10.04 can not currently be unlocked, but would like to have my phone un-lockable at some point in the future to increase the resale value.

I have searched but have been unable to find an answer, I appreciate any help.

[Cer0]

You can use tinyumbrella to perserve the baseband while updating. Otherwise you can use a custom firmware to perserve it and go to 4.3.1 custom for now.