The pattern of feather loss makes me wonder if she's molting. It would be early, but depending on her previous circumstances stress could have triggered it. Agree she looks old enough to lay, she may in fact be old enough to take the winter off and start laying again in the spring.
She was in a pen full of roosters when I got her. Her feathers were all gone in a big spot on her back where they had been broken and rubbed off. She seems to be gaining most back, my hens don't like her much at the moment, but are getting better. I am sure that adds to the stress on her, so I am just waiting to see. I got her with another girl who was in the same condition but that hen passed away from unknown causes. We got two eggs, but the eggs stopped when we lost the other hen. EDIT all my birds are molting and the pen these ladies came from had a lot of feathers, so maybe she is at the end of her molt, as you said. Do they usually take the winter off? I live in AZ.