If you have “Zone Queues” enabled, vehicles that have a job get cancelled are returned to the 1st place in the zone queue again.
If a job turns out to be a “No show,” the system does place you first in queue, but dispatchers (if permitted) can still manually change the zone queue for drivers.
The option “Edit zone queue” can be found in “Settings - Dispatch - 1. General - Permissions.” If this is enabled, the button “Move to front” will appear on a vehicle pop-up in the dispatch console and will, if clicked, move the vehicle to the front of the queue in the zone they are currently in.
https://www.taxicaller.com/manuals/admin-panel/3/en/topic/users-permissions#manual-topic-language