We stayed at the Hyatt Sept. last year for a Magic cruise. When we came back from breakfast, we noticed they were just starting to check people for the buses. This was 30 mins. BEFORE they said check-in was to begin. We checked in, and waited for a while 30-45 mins. or so, and they started boarding the buses (I think it was around 9:30-9:45.) Anyway, we were on the first bus, and it was the first bus to the terminal. I don't think there were more than 5 people ahead of our bus. I think we were third in line to board. Don't worry! you'll get there with plenty of time, if you catch the first bus from the Hyatt!
GBG