Thanks for all your helpful advice & suggestions guys
Is there a resource where I can learn more about colour genetics, it's something which really interests me!
One thing I have noticed is the substantial variation in chocolate coloured orpingtons being use for breeding in the UK, they range from very dark brown, to a milk chocolate colour to a reddy chocolate colour, I wonder if it is possible some are not self chocolate, but the black/dun/khaki variation you mention, or even something else?
I've googled khaki, but can only find examples of khaki ducks, is that the same colour as in chickens?
I will deffo take some more pics & update when we get some feathers come in on the chicks
The only two other breeds I am aware the breeder keeps are light sussex & I think he has some buff orpingtons at POL.
I have contacted the seller, but have had no replies so far.