Thank you so much for this info!Check her really well for lice/mites while you're at it.
I see broken feather shafts and a little evidence of feather picking. Observe your flock to see if the others are picking at her.
One bump (red circle) looks like a feather cyst or ingrown feather follicle, you may want to check that out to see if there's an embedded feather.
Red Arrow is oil gland which looks normal.
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