When will the feathers come back?

[Everlong]

I have a quail that was abused by others and feathers were pulled out, there also was blood and swollen eyes. Right now she is fine, laying etc.
She still has no feathers at the back of her head, only black dots. When will the feathers grow back?

 

[TheKindaFarmGal]

If the feathers are starting to come back, it shouldn't take too long. Maybe a couple weeks. It is kind of hard to say, though, because some birds take longer while others grow feathers really quick.