'100% rise in SOP prices from prior year'. How sustainable is...

'100% rise in SOP prices from prior year'. How sustainable is that price increase? If prices were to reduce to that of the prior year, that would mean the margins on the AISC would be marginal?

KLL could have provided better commentary on the SOP market. I like KLL, I like the SOP market, but their corporate strategy and polish is a bit underwhelming.