Can chickens be molting Now?

My one coop of 19 chickens (2 are still babies & 1 roo) is down to laying only about 6 eggs a day I use to get double+ that amount. They normally free range all day but I had to keep them in just the coop and run one day, found feathers all over. My roo (7 months old, sexually active & just hatched chicks from him) is losing all his tail feathers and his lower rump & brest bone is bright red (with pin feathers on the rump part). My hens range from 1-4 yrs old.
I have checked & rechecked for mites/lice, cleaned the coop top to bottom once a week. They eat organic chicken food. And they each get frontline drops preemptive in spring & fall. I am in western New York, our temps have been very cool (50s) at night and up to 86 (humid) during the day with a few days in the lower 70s. I had an air conditioner for them in the coop throughout July (it just broke & have not yet replaced it) as many of my fancy breeds get overheated easily.
Could they be molting or something else?