I've only suffered PF once, a few years ago... I tried the various boots and straps and socks and wraps and insoles.... then a tri-athlete who had also had it and struggled showed me a simple calf self-massage (the area all around where the Achilles tendon meets the calf muscle, and the bottom part of that muscle) done a few times a day (especially bed time and morning). Mine went away in three days!
That flies in the face of what I was told are the causes... she said (she was told) it's because when the foot structures get overstressed, the lower calf muscles take over some of the work, and once *those* get overstressed, the foot inflammations flare up. So if you can make the calf muscles happy again, they will support the foot muscles/tendons/ligaments better again, and then those will heal. (as I mentioned, in my case, VERY quickly).
Carrying weight and walking long days of course adds a lot more stress, and now I'm paying attention to it... so I usually massage my calves for a minute every time I stop for a break.
And... stay hydrated!