Just to clarify, the BS 1.1 BFS was in relation to producing a...

Just to clarify, the BS 1.1 BFS was in relation to producing a Ni concentrate primary product of ~16% contained Ni, from memory (i.e. in the teens, not a much higher purity intermediate matte which comes later after downstream smeltering). In this respect it wouldn't be too dissimilar to PAN's output, although I cannot recall PAN's actual contained Ni in conc. percetage off the top of my head. (I think it was also in the teens.)

The idea behind receiving ''x' payability rate for one's Ni concentrate product isn't directly (precisely) proportional to the 'y' percentage of contained Ni in the conc. produced. Think of it as being the compensation rate, in pure (spot) Ni terms, to compensate a miner for the effort required to have produced the concentrate in the overall value chain (i.e. from initial exploration to final pure product).
Receiving high-70s payability for a mid-teens primary product might seem disproportionately high until one factors the risks taken (to find) and effort required to produce that primary concentrate.

Nothwithstanding the above comments, kudos for pushing back on the deliberate and incessant misinformation that continues to polute these threads with false cost estimates by another member.