1: O2 does work.. but requires scripting to be enabled.
2: The delivery site was down due to the unexpected disappearance of the script that actually delivers the upgrade after you have registered your upgrade PIN. This is resolved, though I do not yet know why the script vanished.
3: the HSBC site will aggressively check your card details.. if something does not match with what it knows it'll refer the transaction back to us.
4: the HSBC site seems to have problems contacting some card issuers.. if it fails this, you'll be bounced back to us with no money paid.
5: the advantage to us of this payment system is primarily that we nolonger have to have any sight of users card details. It thus resuces the security obligations on us considerably..