The Kode 68 is designed to have an extremely thin tail and this mean that there isn't enough room for both the inserts and the finbox. If we increased the tail thickness, this would have affected the performance of the board so the solution was to offset the back holes.
The back strap needs to be fitted with only one screw on each end (so not double screws) and at an angle: using for example the left side on the front and the right side on the back, when lookng at the board from the deck. It will seem like a strange idea but once you've fitted the strap in this offset way and used it, it works just like a normal strap but still have the benefit of a super thin tail.
I hope this info will be of help to you. Cheers.