There's no set route. Usually it's on a route with POFQ (naturally), often OKW, sometimes SSR, sometimes Pop Century and AOA. Sometimes even Fort Wilderness. Could also be the Epcot resorts (Boardwalk, Yacht Club, Beach Club). The number of resorts on the route totally depends on how many they have going to nearby resorts, in general up to 4 resorts are on the same route - sometimes more if you're arriving very late at night or something. On occasion I've seen five resorts on one bus at midday - but not that often. And that was the 3 Allstars, plus CSR and AKL. But if there were enough people to fill a bus, I don't doubt you could see five resorts on a bus in the POR area.
As for dropoff order, there's no set order to that either. It completely depends on how many resorts they are supposed to stop at and what route the driver takes.