DME is not route based, it's demand based meaning it goes where the passengers on the bus are going. If you were lucky and everyone is going to Music then you'd go directly to Music. However, it's likely that some passengers will be going elsewhere so expect the bus to go to other resorts. But, those other resorts will be in roughly the same geographical area, in this case the southern part of WDW.
I would assume timing means quite a bit. If you're arriving late at night when there are fewer people coming into the airport, DME might not be able to coordinate optimal bus routes and your bus would have to make several stops, in which case who knows if your resort will be first or last or somewhere in the middle. I'd wonder if they prioritize the buses to drop off in order of location (in which case do they hit the first resort they pass and then work their way along a path or do they go to the last resort first, and work their way backwards before heading back out to the airport? Or furthest from the MDE center to closest if a bus driver's shift is ending?), or if they give priority to deluxe resort guests, followed by mods and values? My guess would be there could be many variables and it will always be a crap shoot.
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