I am on the AT&T family plan, and my line is not currently eligible for an upgrade. Another line on my plan is however eligible, and I am wondering if that can be used to get the subsidized iphone price even though I want to use the iphone on my number. I know on normal phone upgrades we use each others upgrades all the time and it doesn't matter at all, but I am unsure on how that would work since the iphone data plan must be added as well. Thoughts, comment, concerns? Anything is appreciated.