Definitely. The only serious winter things to deal with are making sure the rabbits have good shelter, keeping kits off the cold wire and keeping water from freezing. In the summer you have to deal more with with flies and parasites, overheating, heat sterility in bucks, less than prime coats (if you tan the skins), warm waste has more odor so more rabbits=a lot more stink than in cold weather, rabbits seem to have less interest in breeding and you'll have competition in sales from people who breed a lot right around Easter.