I'll offer an opinion that wasn't asked for too........I think you would be better to concentrate on developing your own line rather than trying to keep other lines pure. Once you have made the breeding decisions, they are no longer somebody elses line, but your's! I think you would be beter served to breed the best to the best and keep a rolling 3 pen maternal set up. Pullets back to the pen they were bred from and cockerels roll to another pen. With the diversity you are starting out with, you should never have to bring in other stock, and you won't have to raise nearly as many birds, or keep so many breeders, just the very best....Just My Humble Opinion, that's all folks! .....stan