4Mt @US300 per year w US100 costs would suggest after tax...

4Mt @US300 per year w US100 costs would suggest after tax earnings of ~AUD800 million. Call it 600 million after depreciation & other expenses.

Assuming annual loan repayment of US100 million that leaves annual earnings of 4-5 times the current market cap.

Presumably there will be a ramp up in production but I understand the 4Mt is just an interim target. There's an awful lot of resources.

FWIW I doubt the share price will explode one minute after the road is approved. There will still be scared investors all the way until there is coal being dug out of the ground. But if you keep patient and brave this could be anything.