Appointment rescheduling-when students reschedule their appointments, they are offered the ability to change the start time and the duration but for Centers with fixed start times and durations, the option is still there and students can go through the whole process, only to see "invalid" at the end of rescheduling. This can be confusing and frustrating for students. The option should be removed so when students go to reschedule, they can only choose an existing fixed appointment time and duration for those Centers that have fixed start times and duration.