[Calendar] Please provide a way for teachers to "lock" appointments in the Calendar

[ADuncan23]

I would appreciate it so much if Canvas could find a way for teachers to "lock" student appointments in the calendar, forcing the student to have a conversation with the teacher in order to change the time. Then the teacher could briefly "unlock" the appointment that the student is in and that the student would want to move to. This would really help because appointment shuffling on students' parts without consulting the teacher is really a problem. Thank-you so much!

[ErinMoon]

Yes, this would be very helpful.  I heartily agree!  

Currently, students sign up for a time, then cancel it right before the time it begins and sign up for a later time.  It is too late for another student to take the time.