Just in case you are unaware, there really is no such thing as a mature hair line. The hair line should've stopped moving when your hit your final height. Your hair line is genetic. The receding is based off of conditions being un ideal.
In order to stop the regression of your hair line or to even reverse hair loss, you have to think and understand that it is "conditionary". Your receding hair line or growing forward is symbolic of the follicles going in to a semi-permanent telogen mode. They are not dead, nor are they broken. They are simply comatose. The frontal fibrosis or calcification is the flattener of the scalp. Remove the fibrosis and extra collagen build-up, the follicles reactivate.