The answer is : 20 kg's under SCHRS and 13 kg under Texel.
Wouter
So you keep a handy 20Kg lump of lead in your trailer box. And when you're planning on racing solo, instead of spending 2 minutes rigging the jib, you spend 3 minutes bolting the lump under the main beam!

Result= same handicap as an F16 sloop.......... (and better opportunity to win on handicap)