This Rabbit Breeding Calculator Gives 3 "rebreed" defaults of 45, 60 and 90 day intervals. You pick which date is most ethical and convenient by your standards. I choose to rebreed every 45 days, giving me 8 kindles per year. Most of my "rabbit math" is based on that cycle. Here you can find more info on rabbit breeding. If you would like more info on rabbit output, consult this graph below.
Rabbit Meat Multiplier
Down the side is the number of kindles per year, across the top is the number of does in the rabbitry. The products assume an average of 8 kits per kindle, butchered at 5-5.5 pounds rendering 3 pounds of rabbit meat per butchered rabbit.