Add an ASAP list
The call list and the tickler do not function well for a quick call list. Several steps have to be gone through to get a patient listed. In the edit appointment window, you could have a quick checkbox to add to ASAP list. The call list functions well for those patients that have not rescheduled appointments that are overdue but not those booked already. The ASAP list would be for booked patients wanting a sooner appointment.
Guest
Check box does exist on the edit appointment list to place the patient on the call list. The call list then has a "scheduled" column to indicate they are a future appointment wanting to come in sooner.