Its kind of a crappy diagram but I could find it quickest. If you look at where your highback attaches to the heel loop - 2points of contact. You should be able to rotate the highback within the heel loop. There are usually 3-4 positions or holes u can move those 2 points of contact. Now you can see that in the different positions, the highback will rotate around the heel cup. If you ride an average "duck" stance of say 15degrees on both the front and back foot, and just slap your bindings on in the default highback attachment, they will probably look like the top diagram. Looking down at your board on the floor, the highbacks when up, will not run with the edge of the board but crooked. Now try rotating them so that they run parallel to the edge of the board.
is it late october yet?