Waiting list reserve tickets that have become available

If an event is full and there are people on the waiting list, then tickets that have become available again because someone canceled his subscription,shall be reserved for the people on the waiting list.
At the moment the first one who sees that there are tickets available again can subscribe no matter if someone is waiting for a ticket.

The tickets should be reserved and the first one on the list should get a notification and be able to subscribed within a specific period (like with the link you can send). Or maybe the owner can decide if the available tickets should be available to the public or for the waiting list.