CLA-mining considerations, page-114

Question to all here, what would the difference in start up costs be between a 10mtpa facility and a 4mtpa facility? Let's say hypothetically the final JORC is close to 100mt, and the Cobalt market really does tighten to the point where demand outstrips supply 2:1, surely striking while the iron is hot and pumping out as much as possible in the high price environment would be best? Does anyone think funders/JVers would go balls deep and back 10mpta straight away?

Are start up costs linear? eg. 1mpta - $10m, 2mpta $20m, or do they follow some sort of upward curve where 10mtpa - $200m? (numbers as examples)

As you can see by my post count I don't have much to say as I'm still new to this, I mostly just lurk and try to learn as much as I can from more knowledgeable people. I haven't seen this question asked yet so I thought I'd stick my head up and ask.