This came up a while ago, and I remember there was a good deal of investigating to figure out how to do it, but none of us could at the time - however, I just cracked it so thought I'd share in case others still want to know how. (Have been busy today with a bunch of stuff that required me to make a lot of account changes, and I stumbled upon the option through that).
Anyhoo - if you go to your orders and click the 'print invoice' etc link, you'll have a link that says "edit invoice template", click that and the next page displays the printed address at the top, with an "edit" link to click where you can then change the payment address details (it comes up as the pick up address, which has been removed from the main address menu, so that explains why it was problematic to figure out).
