I have an iPhone X coming Friday and when I ordered it I chose my son's line on my account which is available to upgrade -- my line was used for an 8+ on iPhone Upgrade Program. My plan is to pass my 8+ to my son as an early graduation gift and take the X myself, but wondering what the best approach would be? I'd ask Verizon but I actually think I'll get more trustworthy answers here My thought is to: Activate the X on my son's line. Log into My Verizon and use their device swap process. But is there a better way? Just curious if I were to first pop my 8+'s SIM card into the X before activating it if it would activate to my line, then put the X's SIM card into my (restored-as-new) 8+ if that would activate it on his line? Please comment on what might be the most reliable way to accomplish this. My fear is that using Verizon's device swap process I'd be billed for it, or if there are any restrictions I'm not aware of.