I have two pullets from the same Greenfire line. One is much darker than the other. I think this is due to the original bloodlines from the UK being crossed in the USA. I am certain that there was a line line that produced smaller darker legbars with the waxy cresting on the hens, and one that produced a larger lighter color legbar with the fluffy cresting on the hens. I don't think that the color of Madamwlf pullets is indicative of a resesive color pattern bleeding though. Especialy since the color patter that the Cream legbar is build on is one of the most ressecive color patterns in chickens and anything that is resesive to it is not a color that would be noticable if it bled through. I am sticking with this being some like resesive white the impedes color rather that a resesive color pattern that has poped out.
Also, to reply to another comment, all the Cream Legbars should have cresting, but one out my 3 months old still hasn't crested. She is not correct to the English Standard.