Gets or sets the value to display as the appointment's end date within the editing form.
A DateTime value, representing the end of the scheduled interval.
The DisplayEndDate value is the Appointment.End value of the edited appointment, corrected as needed for the current client time zone (SchedulerOptionsBehaviorBase.ClientTimeZoneId setting). For the Appointment.AllDay appointments the DisplayEndDate is the AppointmentFormControllerBase.End value, less one day. This is done in order to display the correct date for the all-day appointment in the form.