i have heard b.b. red be referred to partridge bred, the color patterns are similar. silver pencilled on the other hand i have not heard of, could be an excellent project for you. you have a great understanding of the genetics, im sure you could pull it off.Random OEGB thought, there are currently 40+ varieties of Old English Game Bantam and probably more that I'm not aware of, and yet I have never even heard about Partridge or Silver Pencilled, that just struck me as odd.