I'm just getting started with Basque Hens (Euskal Oiloa). They are "Columbian lemon cuckoo" or "Columbian barred buff." Basque Hens have Colombian restriction, rapid feathering (k/k), a wheaten base, gold, autosomal red, and mahogany. I'm listing these traits because I don't know what else (other than the first two) might affect the expression of barring. A discussion of EO genetics is here, and some fantastic pictures can be found here and here (the first three pictures).
Anyhow, I want to identify a male who is homozygous for barring to use in my breeding pen. I have read that a homozygous cuckoo male will be lighter in color than a heterozygous male, but I want to understand this distinction more clearly. It is possible that my stock is already entirely homozygous for this trait, but I can't be certain. Any suggestions on how to tell the difference?