Desktop Appointment Diary

Is there a function in appointment manager that prevents gaps between clients appointments? If not, there really should be.

We would like to see a pending request in the "future appointment" tab in client card. SOme way to know that a client calling in has been placed on the pednig list, happens to call in to see if any openings. We fins one but they remain on the pending list because we had no corrolation to be reminded of it and to cxl them off the pending.