I have pullets, chicks, adults, old ones and a adult rooster. And yes they have laid a lot when it was a little bit more hot. No they are not molting and i dont know how many hours they stay in the light.
My girls are spoiled and have still been laying eggs. when I get home in the afternoon around 6 it's pitch black dark but I put on a headlamp turn on the back porch light and the girls are ready to come out lol. I try to let them run around out there about an hour but I stay with them. then I turn off the porch light guide them back to the coop with my headlamp which is really cute to watch. once they are in the coop I turn on the red heat lamp. I have read that it's not good to leave a lot on them all the time because they will eat and lay excessively causing them to burn out on laying at a young age but the light does not seem to keep them awake. by 830 or 9 there for perched and snoozing away. I probably don't need to use the heat lamp as much as I do but I have it set up pointing towards the window on the other side of the window I have 2 other windows leaned up against it making a lean to green house.im in the processes of growing trays of grass and clover.if it works like i plan they will have green to snack on on their coop in the dead of winter.....lol this is the theory of a first year chicken owner ...we will see how it goes.a regarding light a normal bulb on for a few hours after dark should do though