Fixes Issue 625 where the Duplicate calculation would hang if no assigned slots where available.
Fixes Issue 625 where the Duplicate calculation would hang if no assigned slots where available.

Reviewed by: Lennard de Rijk

MatthewWilkes/mw4068-packaging,MatthewWilkes/mw4068-packaging,MatthewWilkes/mw4068-packaging,MatthewWilkes/mw4068-packaging