02-21-2019 09:59 AM
02-21-2019 10:52 AM
I do not think it is possible to transfer in upgrade.
Typically upgrade are ONLY available for a given phone number on a given account. And typically it then requires a 2 year commitment to that account unless you pay it off early.
02-26-2019 08:22 PM
To swap an upgrade, i would go to the ATT store. I've done this a few times, im using someohe else's upgrade on my account as well for the new S10 and i did it in ATT store just to be safe.