I haven't been on (or even seen) an infusion, but generally gybing boards look like this:



When the board is down. The wide back is the only area that occupies the whole case, so the fwd edge is free to "gybe" from port to stbd.

When you pull the board up a bit the max thickness section of the foil enters the case, so that the foil is now locked off on cl.

Hopefully that and my 30 second sketches make sense