Move
Send the vehicle to a named staging point.
Between ReturnToHomeBaseDisposition and ParkInPlaceDisposition in what it assumes: a home base is per vehicle and a staging area is shared, so this is the rule for a fleet that should gather somewhere central rather than disperse to its own corners. Whether that is better depends entirely on where the work comes from, which is why it is a policy and not a default.
The staging point must have room for every vehicle that may go there. A zone holds one vehicle, so a staging intersection stages exactly one and the rest queue on the approach -- which is usually not what was wanted and is exactly the configuration that quietly strangles a model. Stage on a spur per vehicle, or accept that this is a rule about one parking space.