That happened to me one year. I had made some small change in my Verizon account and it wouldn't go through. Had to wait until Verizon was at work to get it resolved. By then I had to wait a month passed release to get a phone. If something like that happens to you it's the middle of the night, you're on your own.I thought about that as well, especially since i'll be using a gift card to purchase (I've never used a gift card on the app before). Seems easy enough, but if there ends up being a problem, i'll be toast.
Needles to say I didn't make any changes this year.