Hey Guys,
I have an iPhone 3GS running iOS 3.0. Baseband 04.26.08. It is currently jailbroken and unlocked. I'm looking to upgrade to iOS 4.2.1. How do I make sure to still keep my baseband and upgrade my iOS? I use t-mobile as my service provider. I've looked through the forums and am confused from what I've found regarding upgrading the iOS. I have no problem understanding how to use redsn0w or ultrasn0w. I'm assuming I'll have to use tinyumbrella? I have windows 7, but can get access to a mac if I need to.
Thanks

Since jailbreaking and unlocking my 3gs, my battery life has all of a sudden become absolutely terrible... is this normal, or is there a bug that something keeps sucking my power?

Could someone please explain to me in simple English how we know if we have "already done a full USB dump or captured your img3’s signed with your ECID?" I just got my 3GS and plugged it into the computer and uploaded my previous iphone's data onto it. Is that okay, or did I mistakenly lock it forever?