This doesn't sound right to me either - 1 is young to start breeding. The KC breeder I got my puppy from wouldn't consider breeding her bitch until 3/4 years of age for the peak mental and physical maturity needed for a healthy pregnancy and being a good mum to the pups. Having an 18 month old bitch myself, I couldn't imagine breeding from her 6 months ago - she was still developing and very much an adolescent. I could be completely mis-judging the breeder here and they may have their reasons, but I would always say if you get a funny feeling about it/see any red flags then walk away from the sale.
Good luck with your puppy search! It sounds like you're going about it the right way doing your research!