David has it right, mostly.
For MK, normally 2 buses:
- Yacht & Beach Clubs for one;
- BW, Swan, and Dolphin for the other
For AK, normally the same as MK from 1 hour before park opening until 11 a.m.;
and Swan, Dolphin, Yacht, Beach, and BW the rest of the day.
For DTD, it's always Swan, Dolphin, Yacht, Beach, and BW.
For MK, and for AK mornings, there will be a few buses mixed in that do all 5 resorts starting at the Swan.