I have four BO pullets, 19 weeks old, and about a week to 10 days supply of grower crumbles left- I really don't want to buy another bag of grower crumbles and only use a tiny bit of it. Would it be harmful to just switch them to layer feed when grower runs out, when they are 20ish weeks? No eggs yet, but a few have combs that are really getting red. also, someone please tell me the eggs will be here any day now!!!!