I probably got it wrong I saw the following on the Spitfire site. I assumed that they had made another one.

"RYA Dinghy Show 5th and 6th of March Alexandra Palace. See the new Spitfire Video and come and help on the stand to promote your class!!"

I supose that it is logical that the SL 16 would have some of the same parts as the Spitfire when Yves designed it and Reg is building it.
Dermot.