It took forever to get better (about 1.5 years from initial injury to resolution), but the following really helped.
-nightly stretches with one those of stretchy exercise bands (not the rope, but the sheet)
-nightly toe raises (gradually increasing reps, moving from two leg to one leg as you get stronger)
-nightly calf stretches
-gentle but consistent calf stretching immediately upon waking (essentially stepping out of the bed into a calf stretch).

Good luck with PF! It's a tenacious beast.