When you get on the ship there will be a gift card in the cabin. On the night you wish to use the wine take the gift card with you to the dining room, choose your wine from the wine list and give the waiter the gift card. The charge for the bottle of wine will appear on your statement and then it will be removed. If you choose a $20.00 wine your balance for that bottle will be zero. If you choose a $30.00 bottle of wine the $20.00 will still come off your account and the balance of the $10.00 difference will remain on your account.
Is that as clear as mud???? :grin