ATL: Sterling 738 @ DL Mx

Passing through ATL last night in the dark and rain, I noticed a RAM 763 and a Sterling 738 at DL's mx facility out beyond Concourse E. It looks like the Moroccan is CN-RNS, which ferried down from JFK a few days ago. The Sterlings are a little tougher to track down since the fleet was dispersed after their bankruptcy. Can anyone confirm if it's the former OY-SEK, now 292AG? Also, there was an all-white 752 sitting on the apron in front of the building. Anyone know what that might be?