Huh; well, I don't think they're speckled sussex. The specked ones are much darker, a chocolate color, and the chicks have those "chipmunk" stripes. Maybe a cross between buff and speckled sussex? You might ask the breeder if a speckled rooster could have gotten to the hens for awhile! If that is not the case, then my limited expertise (HA) is exhausted, and it's time for a real Sussex expert to advise!