I am on a plan with my family, and want to upgrade one line (A) using another line's (B) upgrade. We have done this succussfuly many times in the past, but the most recent time we had a different experience. Line A used line B's upgrade to get an iphone 4s. After purchasing the phone online at att.com, we went into our local att store to get the phone activated for line A. In doing so, they said that line B (also an iphone) would need to replace their sim card. We did this and everything worked out fine - line A got the iphone 4s activated and line B insereted the new sim card in their phone.
Here's the problem - in the case of this potential upgrade swap, Line B is out of the country so getting a new sim card for the phone would really be a pain. Can we still do the upgrade of liine A without having to replace line B's sim card??