Keywords: requests, hold queue
When all the copies of a book are unavailable (checked out or otherwise not available), the user will ONLY be asked if he wants to place a hold if the following criteria are met.
There is at least one checked out copy among the unavailable copies.
This checked out copy is due in less than 10 days OR is not overdue more than 10 days.
And there are currently NO holds on this copy. Only one hold is allowed on any copy.
If any of these fail, then the user will be told that no copies are available for requesting.