Gonna guess you meant 10 pullets plus 3 older hens?like maybe 3 weeks before hurricane Michael hit
so that was like September 10th?
10 5 hens (not including the three veteran hens) 5 roosters
So there are 3 older birds? Is one of them the bully?
Were the 3 older hens living in the coop when you moved the younger ones in there?
FYI.....semantics, maybe, but can be important communication terms when discussing chicken behavior.
Female chickens are called pullets until one year of age, then they are called hens.
Male chickens are called cockerels until one year of age, then they are called cocks(or cockbirds or roosters).
Age in weeks or months is always a good thing to note.