Change number of attendees when rescheduling bookings
I've had a couple of sessions where people have booked in for X amount of people and have then either reduced or increased the number of people they'd like to send. Currently there's no way to edit their original booking to comply with this. Not necessarily a problem if they're adding people (I can just create a new booking for the extra people), however it becomes an issue when they're removing attendees and I'd like to free up those spaces for new people to join the class.
