Originally Posted by
PLeblond
I don't recall the credit card holding the amount as one can request an eUp months in advance. Maybe a $0.01 type validation to ensure the card is valid. But if the card is declined at time of transaction, I'm thinking the eUp would not clear.
I've been SE since before there were eUp addons, and I haven't flown Standard on a multi-cabin flight since then either, so I definitely have no experience.
That said, I have worked places that would place a preauth charge on credit cards for the expected amount (which verifies it's available), and if we ended up not going through with that customer, we just let it expire or explicitly released it.
A $0.01 preauth just verifies the card is active. A $200 preauth verifies the card could withstand a $200 charge (today).
But I'll let someone with more add-on experience comment on this.
I do know for a fact that pre-Amadeus, a friend flew on a gate eUpgrade with an add-on, their card was subsequently declined, and AC came after them for the money (not in a "bad" way, just "hey, this happened, you owe us $x"). So pre-1A and pre-new Aeroplan, it was definitely not a "charge at time of clearance and don't give the upgrade if it fails".
Processing a credit card is probably too slow to do it during auto-onload. You might have 20 of these people. It's a network call to a third-party vendor. Too much risk that it doesn't work for reasons other than "card declined".