I've raised meat birds (Vantress) for 2 years and I believe that raising them in middle to late fall (Aug, Sept or Sept, Oct) to be the best and most cost effective. I lost two when I raised them in April and May one year and the next year I tried May and June which seemed to work better. Didn't lose any. I don't keep a light on in their coop, and I don't feed them at night either. They just seem to be healthier and happier. I take 1/2 in to be butchered at 6lbs., usually the males and I take the last 25 in 1 week to 2 weeks later at around 7lbs. My family calls them Frankenchickens, and I really enjoy raising them and they are juicy and tender. I'm always learning and hope you don't give up.