Is it possible to book a rate with breakfast and pay to upgrade to either full board or all inclusive at check-in? If yes, do you know how much for a single? I'm thinking of booking on booking.com because of the Aadvantage miles awards, and their full board works out to over $300/day extra! Argh! And any thoughts about it's worth booking via booking.com for 44k Aadvantage base miles? The price (not all inclusive, just the base price) is comparable to booking through the Marriott app, but those miles could take me to platinum pro or beyond....