I don't know if any of you have ever done what I'm about to ask with any of the other iPhones but I'm hoping one of you guys can help me. I'm on a family account on AT&T and a relative has one as well (different account). I want to use my relative's upgrade on that account and use the 4S on my line which is on a different account. I will pre-order the phone and get it delivered using the account and number with the upgrade but I don't know the process they do or what I have to do. I'm assuming that the phone won't be activated until I receive it and activate it. Is that correct? Will I need to do anything on that account before I put my iPhone 4 sim in the 4S?