It depends.
MK I believe always has a dedicated bus since both POFQ and POR have their own bus stops at MK.
For the rest of the resorts, the busses will sometimes go to POR after POFQ but they do go to POFQ first. My experience at different times of the year has been that first thing in the morning before the parks open, the busses never went to POR after picking up at POFQ but frequently did go to POR after POFQ later in the day (slower time of day). Going back to the resort at the end of the day, POFQ gets dropped off first so it really doesn't matter since you don't have to drive through POR anyway.
The DTD bus goes in reverse and goes to POR before POFQ. Unless there's thunder or lightening, you can take the boat from DTD though if it's raining, you'll get pretty wet.