Okay I was incorrect it started after 7th year molt
https://www.feathersite.com/Poultry/CGP/Phoen/BRKPhoenix.html
Still could be related in a way to what you have going on but earlier.
https://www.feathersite.com/Poultry/CGP/Phoen/BRKPhoenix.html
Still could be related in a way to what you have going on but earlier.