commiserations on your PF
I got it 12 months ago and unfortunately it took a while to go from a ignorable niggle to a proper pain that i couldnt run with and therefore sought professional advice.
i was given a regime of stretches and took a few weeks off. resumed in time to do a few 20 milers before FLM and all was fine (but slow).
Then a few weeks later it crept upon me again. this time i got some off the shelf inserts (£30ish) which i used 100% of the time (daytime and runs)
These seem to have sorted it out as when running I now cant even tell which foot it was. I still get aches and some pain after running though.
Bottom line is - it will take a long time to be fully gone and you should do heel raises and calf stretches.
Incidentally - I never got a satisfactory answer as to the cause of PF anyone any ideas?