Kayleen: They've had plenty of time to get used to each other. Do you ever let them free range? That's an excellent time to let them mingle where they have plenty of room, and plenty of diversions to keep their minds off of beating each other up. I assume you have plenty of roost space available? Has there been any blood shed when they've been together, or just a lot of chasing and pecking going on? do you have 2 or 3 feeding and watering stations available. That will help, as well as, when you give treats, fling them far and wide so they all get a chance to get some of the goodies. You're going to have to let them duke it out. Unless there's blood shed, stand back and let them work it out. It's more stressful to us owners than it is for the birds. Pecking order... it's what they do! It will also go easier if there's plenty of places for the younger girls to get away from the older girls. Give them some hay bales, some pallets, stuff to hide behind and under. If you have a strong alpha hen, you might need to remove her for a bit, then after the youngsters have integrated, allow her back in. Or, you could take a couple of the lower pecking order hens, and put them in with the pullets. Keep adding hens to pullets until about 1/2 of them are together, then put the whole group together.