I'll let Bernard answer in more detail, but we don't have 4n+ yet, we just have "extrapolated" (ie. PYR has calculated) that 4n+ is possible at commercial scale with low purity feed. If the terms of the Taiwanese deal were/are in play, I think 4n+ would need to be demonstrated with actual material samples. This is what we are all waiting for with the Gen3 pilot plant.
4n+ has only been confirmed on paper.
Cheers.