Well some are lighter and some are darker, yes, but I don't think there's a difference in dun vs khaki as I'm sure the Buff dad is carrying khaki. (homozygous dun) - All of them are shades of yellowy, one is pure Buff looking, the others have a faint dot or two on the head, which is normal for this cross. If anything a few of these don't carry dun at all and one does. But I doubt that's the case.
Proof hatched out though that this isn't a fence jumper issue - Got a chick that came out obviously the offspring of my Am x Polish cockerel, as it is striped quite well. (influence of the patterning, columbian, or both genes) Clean shanks though.
The hatch is done though, got just the four, all feather shanked. I marked the best of them, feathered shanks excluded, (although it has the lightest feathering) and I'll see if I want to keep it for experimentation or not. Otherwise. . . Looks like I'll just keep hatching more.