LeadTurn_SD
Contributor
..Now I am starting to wonder if these are supposed to be on the belt near the backplate, securing the shoulder straps at a fixed length?
That is how they are typically used (to "fix" the length of the shoulder straps). They are positioned on the back side of the lower slots of the plate (if that makes sense).
But others intentionally do it the way you have yours rigged, so in the end it is whatever works best for your diving.
Best wishes.