​@Mhughes there is no direct way to exclude specific customers when running this action. However, you could think about defining Customers and setting up different priorities in the Sales tab. Then when you run the CUstomer Order Reservations, you only select the Priorities for which you want the job to be run.

Let’s say the customers for which you want to run CO Reservations have Prio 1. The rest have prio 99. Then when you run the job, just select prio 1 CO headers.