i plan on backing my 13 pro via iTunes and then restoring the backup to my new 15 Pro, My question is this. Since the 15 Pro has no sim tray. How do I transfer my phone number to the new phone? I saw some videos on YouTube that shows that if you hold the new 15 Pro next to the older phone then a Prompt will pop up asking you whether you want to transfer you phone number to the new phone. Does that work with AT&T prepaid or am I required to go to an AT&T store to get my number moved to the new 15 Pro?