Guilford units in Binghamton yard?

i recently saw a photo showing a guilford units in the conklin yard in binghamton. whats the deal with that...do guilford have regular freights to binghamton or are they leased units?

http://railpictures.net/viewphoto.php?id=33769

The 380 and 381 had been on lease or where trading back hours to NS. I caught this unit and its mate on the NS local that worked between Allentown, PA and Washington, NJ last year around that time. They had been on the NS system most of last year.

Chris