I've ordered new iPhones from the Apple Store in the past and it always defaults to the AT&T billing address for shipping. You've always been able to go in and change it after the fact from your order status page or by calling Apple. However, this year that is not the case as the status page has it locked and I spent 45 minutes on hold with Apple only to have them tell me it can't be changed if you're on AT&T. I know there are probably other people out there like me who are on family plans and don't live at the billing address.