how long did you grow out your birds? I proccessed hatchery BR dressed at 4-5lbs at 20 wks1. I am pretty new to all of this as well, but I am a little bit ahead of you so I thought I'd chime in since no one else has.
2. There direction I am taking is different than yours. I am using only heritage birds because I choose to fight the big corporations and the modifications they have made to our food supply.
Last year I raised and then processed hatchery purchased dual-purpose birds. That was a complete failure. 13 birds total did not give me 10 lbs total. 2 carcasses are only fit for broth. The rest won't feed 2 people each. Crying shame because they were good layers with wonderful temperments.
This year I've changed directions. I have set up my own breeding program with red dorkings ... A rare, heritage dual purpose that "the man" hasn't put his paws on, lol. I'm just starting with this, so no one has gone to the processor yet.
My dorkings have their own coop (thank goodness for heat lamps during this frigid period).
I have layers left over from the other effort that inhabit their own coop.
I plan to set up a small scale breeding pen this spring when the girls are closer to sexual maturity.
Good luck in your endeavors and it will be nice to have someone to compare notes with.
I find this study ineresting https://projects.sare.org/project-reports/fnc12-866/
also some of us have been holding a smaller cx hen back.. have to start restricting feed at 1 week and free range them with the layers to get them to live long enough to lay eggs. some people breed the cx hen to a rainbow or ranger. I just use my mixed roo.. most of mine don't grow any faster but have about 1/2lb more of breast meat. some dressed out at 7lbs at 19 wks