Waitlist for full day + when customer cancel apointment, a notification will automatically be sent to people on waitlist

Hi, I would like to request a feature where customers sign up for the waitlist for a full day rather than a specific time. Since we have a very limited number of bookings, clients are often flexible to book in, and they often request to sign up for a full day. Please let me know whether this is possible. It would also be great if the notifications are automated, so when a customer cancels or reschedules an appointment themselves, clients on the waitlist will automatically get notified. We have lots of clients on our waitlist and it would be very difficult to go through it all. I really hope this is possible. Thanks in advance.