I guess you have the SUP board with the mast track (slot) in the deck vs the SUP with the 2 inserts (like the 12'6" I have).
Ellen and I were looking for where the foostrap inserts are, and I had to write to Tiesda You at Starboard HQ to discover that there are 2 different "flavors".
The SUP boards with the mast slot have FS screw inserts and the insert holes are opened up and easy to locate.
The SUP boards with the 2 mast bolt inserts do not have any footstrap inserts at all.
Hope this helps someone as it was something I didn't know and probably never would have guessed.
Hope this helps,