I have one 12 week old chick. I am about to run out of chick starter for her. I have 7 other adult hens that I feed layer food. Do I really have to go buy another 50# bag of chick starter at this point? I know they are supposed to be on it for 16-20 weeks, but I'm wondering if it is that big of a deal to switch her to layer at 12 weeks? Thanks.