One of the problems of integrating a flock is feeding them. There is a danger of too much calcium for little chicks if they eat calcium-rich layer food too soon. On the other hand your layers need calcium to lay eggs with fully developed shells. I only maintain a small flock of chickens and don’t need or want half-used bags of chicken feed left around my shed.
Here is my solution. I allow my new chicks one 50 pound bag of chick starter. Once that bag is gone they go on an all-purpose flock raiser feed. Flock raiser is an all purpose food, not perfect for any type of chicken, but it will work, sometimes requiring supplements.
During integration I swap my layers over to flock raiser as well. Layers require the supplement of calcium with flock raiser and I use oyster shell during this time. If my young ones have any chick starter left I continue to fill the feeder in the youngster’s pen with chick food until they finish off their bag. Then they too will move over to all purpose flock raiser food. Life will continue on this way until the first young one lays an egg, then I will let them finish off the flock raiser feed, and move them back to layer pellets.
Come late summer I will have only one type of feed left and it will fit in my mouse-proof can. No problems and a healthy flock of layers for the winter.