I am buying 10 new Black Sex Link pullets this evening and have a run/coop separate from my other 17 chickens. The BSL's are 7weeks old and my current chickens are 9.5 weeks. What is the best way to "introduce" them to each other and eventually both be in the main coop/run. I think that I will let them free range together tomorrow evening while I can be home to supervise.