It could be the change in food, I switched food this summer, still layer, but a different brand. Odd thing is, one of my EE has gone stronger color, and one of them has gone nearly white. It could be a cycle thing though, the EE whose color improved started her molt first, and slowed laying, but never really quit, and has gone back to regular laying since she has nearly finished molting. Neither of my girls lay every day though. I have one RIR, and the color of her eggs varies somewhat from day to day.