It's always good to assign queues to teams, rather than users.
By default jobs submitted go to Normal queue. However there are other queues like Priority, Short, Night etc. which can be used for specific purposes.
I have seen most of the GRID users are not aware of the default available queues to submit their jobs. It's good if you educate your SAS users about the default queues available and how to submit jobs to those queues.
Kindly check this document for reference on how to submit to specific queue.