I just read that your roosters are a new addition, your hens may not be totally used to them and it could be causing some stress that’s reducing egg laying as well.
How long ago did you add supplemental light? It’s possible they’re still on the reduced daylight schedule and haven’t gotten back with the program. Even with the light I would expect to get fewer eggs through the winter than you’re used to.
How many hours of light are they getting? And what breed(s)? Cold doesn’t necessarily slow them down too much, it’s the daylight hours that trigger more or less egg laying.