The problem is that the ends of the board are too thin and bend along the thicker part of the board
My 2006 Nobile did the same thing, bent along the raised contours at the tips. I sent mine back and got a new board.
My 2007 Naish Thorn did this also, snapped along the contours in the tips, didn't get a new board this time though
Which is why I will not buy another board that is made in the same way as Nobile and 2007 Naish - ie foam core construction with the layered contours at the tips
they just can't stand up to the kind of usage that I put them through.
I've been riding a Naish 2008 Thorn with the full wood core and carbon fibre reinforcements and haven't broken it so far
PS I'm 14 stone and busted my last 2 boards kitelooping