Check-out is by 11am, so yes, you're going to leave your luggage at Contemporary, but let's work backwards:
1.) Orlando airport can have long lines for security. You need to be there by 11am'ish - easy?
2.) Need to be picked-up by 10:30'ish to make that work.
3.) Need to finish breakfast by 10'ish to make getting back to Contemporary for 10:30 (yes, you're taking a taxi, because I'm spending your money if you can afford the Contemporary and feel the need to Bon Voyage).
4.) You'd need to arrive at restaurant by 9'ish (or earlier) - to have the hour to eat that Disney wants you out by.
5.) Need to leave Contemporary no later than 8:30 (by taxi - because I'm spending your money and resort-to-resort takes too much time - which is why we avoid these things) to arrive before 9am.
6.) Bellman needs to take you luggage before 8:30am, so you can be early for the taxi (that I keep spending your money).