Dunno what else may be happening, but with the general decline in demand for coal, PSNH might be finding itself in a very advantageous pricing position. In earlier years, the cars for Bow service could be and frequently were a hodgepodge, including leasers, some of whom had SLSF branding ghosting through the paint-overs. More recently, the 88 have been all NS or NS plus a few CR, and aluminums, which had been a rarity around here, have become far more frequent and numerous, possible indications of the increasing availability of company rolling stock and the increasing relative importance of Bow.
"A gray crossover is definitely not company transportation."