I won't reiterate what everyone else has said, but will add my opinion and observations: Kidani is the resort you want for guaranteed seating on the park buses. When the bus swings around to Jambo after Kidani, those remaining on board from the trip back from the parks exit and free up space before the Jambo folks can board. I have seen folks stranded at Jambo with the bus too full to hold more. I've never seen this happen at Kidani. This has only been over that week from Christmas to the new year, and the real issue was Disney had too few buses operating. Guests should never be left stranded at a deluxe resort bus stop.
Note, If there happens to be an ECV or two at Jambo, those in those seats will be asked to move.
All of this is really no different than staying at a larger resort such as SSR or OKW: Those at the first bus stop have the base chance of getting a seat. AKV in general does have the best bus service of all the DVC resorts. (BWV being the worst, but they have boats and walkways to DHS and EPCOT)