I had it maybe 12 years ago. It was excruciating in the morning due to sleeping overnight with my feet pointed down. I bought one of the boots that holds your foot at 90° and got almost immediate relief. It was a game changer. Got it from Amazon. I’d guess that it was completely resolved in three or four months, but I wore that boot for probably seven or eight months. I was already used to it, so there was no downside, I slept fine. And the PF pain was something I never wanted to experience again. I still have the boot, I wore it a few times over a couple of years afterward, just when I felt any sort of pain there, not wanting to take any chances.
I went thru a couple iterations of the boot before I found one comfortable enough that it didn’t wake me up. The biggest boot was the most comfortable because there weren’t any concentrated pressure points. It supported the whole bottom of the foot and well up the back of the calf. Good luck.