Hi, UPS told me when my pkg is return delivered I will be billed online accordingly.
It doesn't matter to Sheffield how you pay/or the arrangement you have, they just want the responsibility of the ship costs to be yours , not theirs.
I just used the entire address with International Operation and Visa's as the name line.
UPS also asked me for a UK PH # for the delivery address. I didn't have one but gave my fiancés number. She explained the computer just needed one to recognize in the country of delivery. It worked and the bonus to me was if there was trouble with delivery etc, they would contact him which is better than it being somewhere it shouldn't be.
I created my own prepaid label at home (to be billed for when delivered) and for the outgo to Sheffield I went to the UPS store, sent Express on Fri , was delivered by 9AM on Monday and they were great & had it ready in moments.