Adding corn reduces protein and increases fat, over most standard rations. You can feed what you like and I turn it over to the experts, but I would stick with your more complete ration, rather than trying to mix and match.
Anything in the PM line called Breeder/finisher is 20% protein. Not really a dimes worth of difference between the 2 unless you are expecting eggs.
Add corn, and you lower the protein, and increase the fat. I'm not saying that is a bad thing, just something to think about.
I'm an (Out of the bag) person. If my birds ever became to costly to maintain over the winter, I would eat them, and start over in the spring.
That's just me.