Southern's usual practice was to repaint the white tires and sometimes even graphite between runs. It was part of the usual servicing that they always did (coaling, water, inspection, washing, light maintenance). This was quite often. For example, Southern would doublehead Ms-4's from DC to Spencer. Take those two off and service them for another run. Put two more on the point to Atlanta and do the same there. It kept fresh, clean locomotives on the points at all times.