You know, I am glad you made this post because I just posed the same thing with my quail, and they stopped laying due to this heat wave that is coming through. I totally believe it is the heat, because it is the only thing that has changed. They are all fairly young, I give them greens and vitamins, they have a nice dust bath and chopped hay to roll in. The even have a shady place to hide out of sun. So for me I am sure it must be the heat. Tell us when your girls start paying again, and if that started when the days became cooler. Very curious.