Thanks to a heads-up from Nick P., I made it out to Woods (west end of a passing siding near Front Royal) and saw NS train 90M with NS SD60E #911 leading a short train of tie-gons. First, train 13R headed east by the control point into the siding with ES44-AC #8117 and D9-44CW #9480 on the head-end and ES-44AC #8079 pushing on the rear. Then, 90M came west to drop the gondolas at Front Royal. Pictures and a video are below.
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