Ok. But my confusion lies in that the first picture shows 483 (w/plow), 480 (w/o plow?), flanger, spreader and two cabeese. This appears to be between Alamosa and Antonito ( I do not know where but I bet some here know exactly where that is).
Picture two is pointing to the "end of standard gauge" with 480 and the flanger having traded places.
Picture three has the flanger and spreader having changed places. Thus the original question by Mr Loco being when and why? Between two and three.
All three show a different order for the same train that then does not add up.
Phil