My mother asked me this question, and I wasn't sure of the answer so I'll pose it to you guys. I'm sure it's in the terms of sale, but I don't want to get to that point in the process if the time is too short. Anyway, my mother wants to buy an iPhone 4 for my brother for a Christmas gift. He is on her family plan with AT&T, so it wouldn't be a problem with her doing the actual purchase on the account. She wants to buy it online at Apple's website as soon as she can so she doesn't have to worry about possible short supply as Christmas nears, and also doesn't have to deal with going to the AT&T or Apple Store. The big question is, what is the length of time you are allowed to wait before you activate an iPhone that you've purchased at Apple's online store? It is an upgrade, so perhaps there is no time limit, but she just wanted to be sure. Thanks guys, I appreciate it.