Um, that's good point.

They "shouldn't" have barring, but some of them clearly DO have lines of white across the wings.
Some colors of chickens have markings like that when little, but a different pattern when they grow up (I've seen it in some laced and double-laced chickens, for example: they had lines like that when little, but pretty lacing when they grew up.) But even if that was it, I would expect the lines to be in gold and black, not white and black.
I'll be curious to see how they look in a few weeks and months, to see how it changes as they grow, but for now I have to admit I'm stumped