PY Ratings for Boards?

I'm wondering if any of you have boards racing alongside the boats at
your respective clubs and if you have issued PY's for them.

I've got a list I'm drawing up and I'm hoping to get a Single Hander Night
going next season with Boards up against stuff like Lasers, Contenders,
MPS and whatever S/H I end up organising for myself.

I'm awaiting some data from Grafham where I know they do this, but the
more intel the better.

I also suspect we may have to split the rating, some boards react so very
differently on and off the plane, probably around 15 knots windspeed,
has this ever been suggested/tried boats like that V3000 for instance
acts very similarly to a sailboard due to its light weight and small wetted
footprint when it's windy.

As to the split PYs- I believe the US Sailing PY system does incorporate this, but it is fraught with difficulties. What windspeed do you use? Forecast? Average through the race? Minimum recorded? Speed at start? Speed at finish? Average of those two? Average of speeds recorded at set intervals through the race? Maximum gust? What if a race (and even hour-long races can fall foul of this) starts in a lovely force 4 and has dropped off by the finish to a force 1 drifter? Even on the sea the wind is not consistent.

The Return form does ask for an estimates of wind strength, and the RYA has expressed in the past a desire to issue differential PYs- for wind strength, and/or for different types of venue (the example of the latter split them into Lake/Reservoir, River, Harbour/Estuary and Open Sea), but also recognised that to do this well they needed more data.