Originally Posted by
SnapThrow Kind of what I was thinking since the SIMs are compatible. I'm just not sure if I need to activate the 5S with the SIM it comes with first or if I can switch the SIMs and activate/restore after...
I would simply activate the phone as they sent it to you... then swap the SIMs and be done with it.
BTW, the only time I’ve ever had to visit an AT&T store for assistance with this was going from a BB to the iPhone 4 and again going from the iPhone 4S to an iPhone 5 - any only then because of the change in the size of the SIM.