I just changed this to 6 slots per hour ie. 10 min slots so that allows for both 20 and 30 min appts. Probably should make it user configurable.
Finally got around to allowing users to add appointments from the web portal ... find some use for those iphones people have!
The following are now possible: 1. create new appt ( not linked to a patient though ) 2. delete appt 3. move appt 4. change the time/date and details for an appt