In the future... You can always change your payment method after the fact. Get the order in and worry about the specifics later.
This happened to me during my order. Got in right when the App Store went live (3:03am EST) had the item saved as a favorite ahead of time for quick purchess and went through the order process used my Apple Pay click submit and bam it said my billing information was wrong. So went and interred the address format my DL has and then went through (no way of doing it after the purchase wouldn't allow me) so instead of a 04:00 or 05:00 time with a chance at the 4/24 a5/8 slot I got clocked in at 08:11 and moved into the 5/13 -5/27 slot. Though it didn't cost me too bad it still should of been brought to my attention when I set up Apple Pay a week before.