This is a good option and one the management would be...

This is a good option and one the management would be considering. Perhaps not a public usd RegS as it would be far too expensive to get a rating and set up the program for a one off issuance. The public market often locks you in with a decent makewhole and non-call period. Similarly issuance in aussie market wouldn't work, investor base isnt deep enough.
Usd pp could work given it is relatively low cost c.usd100k, they have been travelling to asia, JB is familiar with singapore and hk, the go to places for RegS, 144a and pp.
A top up and termout to 5 years, 7-10% coupon plus a small working capital with one of the domestic banks to build a relationship.
Get to nameplate, demonstrate low cost production, lock in offtaker and there will be multiple options, prepayment, bonds, bank debt, cr or most likely some mix of these to refi and fund stage 2.