How bookings work — Who can do what
• Anyone with the public link can book — that is the point of it, and it is why the link is long and unguessable rather than a login.
• Creating or changing a booking page is an admin action. It mints a public address, so it is not something a member does by accident.
• The scheduler is readable by anyone who can see the table. Dragging, reassigning and setting a status each need write access to that particular field, and the control is simply absent where you do not have it.
• A customer holding a manage link can move or cancel their own booking, and nothing else.