BFS raise amount

I am curious as to how much more capital, shareholders (or non-holders) think will be required to complete the BFS. Specifically the quantum of the next capital raise.

I have a number in mind but I don't want to influence the thinking of others. Just on the back of an envelope I would say funds are needed for:
- further drilling to confirm the resource
- demonstration plant run
- pit optimization and plant size design for a smaller operation (at least initially)
- pipeline design and required facilities etc at Broken Hill
- rail to port option and back to transhipping by barge?

What size mine will the revised BFS aim for? I would suggest 5-8 Mtpa given the reduced capex expectations and the (suspected) limitations around rail availability.

Thoughts?