Hi I've a 16gb iPhone 3g which I've had since October 08 on an 18 month £35pm contract. What is the best way of upgrading to the new 3gS on O2. I intend to sell my 3g, its jailbroken and unlocked and is using 3.0. Will this be my best option if I can sell my 3G for around £300, If I downgrade my contract today to £29 and then the day after pay it off and buy the 3GS. How have you guys upgraded on O2 and let me have your thoughts on my idea.