,Hi,
Well according to Greg Brereton a Light Sussex will not have a black hackle if it is missing the Hackle Black gene. It will have the other black points but not the black hackle. Hackle Black gene is still a theory tho. Greg did a lot of research on it and believes it exists.
As to the legs, Light Sussex can be hatched with light yellow legs which will turn white as they mature.
I have Light Sussex and have never heard of a Light Sussex in the USA or Canada which has not had a black hackle. You should be seeing indication of black hackle by now. Your birds are out of the down and in juvenile feathers by now? I think you have foreign blood in there somewhere. Or this could be a European thing. Were the chicks in down when you received them? A proper Light Sussex chick down is pale yellow. Spots, dots, or any kind of discolored feathering is unacceptable and is warning blood of foreign blood up close in the pedigree.
That said, these are newly arrived European strains so you may want to give them another month to see if they are just developing plumage at different rates than we are used to in the USA. But if the legs are not white by the time they are fully feathered out in juvenile feathering, your have foreign blood in there.
One other thing, when your birds are grown, the down is white to the skin. If the underfluff has a hue of color to it, it is absolutely indicative of foreign blood in the bird.
Best,
Karen
