By Refining , I think it implies the use of a furnace and or leaching up to a marketable grade for pure copper & cobalt not just a 3 -6% cobalt copper concentrate that would be achieved by a mill and a flotation circuit.
Not sure where the proposed acid leaching of tailings fits in there,but, it's a bit of a curve ball for all DRC resource plays AVZ 4CE VEC NZC will all have to make adjustments to their process flow design .
Not really sages fault at all . All of us want to buy low and sell at a premium .
No one would blink at a few bags for a high quality Cobalt asset a year or so on .