Did not try the freeride 12'2" windSUP yet (it's on my to-do list), but I surmise max speed is related to the scoop-rocker line and the positionning of the mast base.
However, I did try the SUPer 10'0" with a 6.9 m2 sail in planing mode in ± 15 knots wind (see http://www.star-board-sup.com/forum/...ad.php?t=12089
for a summary) and found out that it was extremely difficult to start and sustain the planing with the mast base set on the front-most insert. When mast base was further moved to the back of the board, no problem to start and sustain the planning. Speed and acceleration were OK, but not dragster like à la iSonic of course... One can even do wide turn carved jibes.
So, my guess would be to move your mast base more to the back of the board to increase the planning and top speed. Something like 130 or 140 cm from tail's end ?