Good questions. We talked about this at length last night and this morning. Both Easton and JC boats were gone over carefully and in detail before leaving the beach for the last race. Greg feels very confident that it was square when the boat was stood up, but you never know. Two theories 1) When they righted the boat on the beach the person walking the mast up walked it up along the diamond wires as apposed to the side stay, and might have bumped it up. 2)the head of the spin in the spin set could have got caught on the spreader and been forced up when raising the halyard.
When the boats left the beach they were all on the same tack and downwind, making it unlikely that Tripp yanked it up with the halyard, as the picture showed it was already that way. So it was likely yank up in a previous race with a different team on the boat, or done on the beach. I don't think it is likely that it got moved on the beach as the diamonds were set on 33, but who knows.