Student booking conflicts - similar flag to personnel conflicts

The recent updates to Instructor admin have been great - we can now easily see when an instructor has been assigned to two events on the same date/time. 

It would be great if there was a similar function for Delegates - it's currently possible for us to accidentally book a student onto two events which clash, and it only gets picked-up if someone happens upon it/the student replies to their booking confirmation to flag the issue.