Were those cases current gen systems? Are the part numbers marked with the FC prefix? Also do the first three digits of the serial number conform with the refurb designators?
The reason I ask is because I know for a fact that if Apple takes too many orders for a particular current gen refurb model, and doesn't have the stock to supply them, they send out a brand new one instead.
Mine is a current gen-17" i5 with AG screen.