For any of you out there that have ever started up a small business.. other than property and material initial costs.. the grand opening is always the highest in cost startup. If you have a brand new location, brand new gear to operate ... what are you still missing? .. Trained workers. IMO, the reason for the additional funding would be to allow for financial flexibility to train operators of their plant, and the first time period of purchased contracts to become revenue received ... IE .. your workers get paid time now (first quarter of operation), but receivables (income) is not realized until the contracts are fulfilled.. which in normal timeframe especially for a miner .. is about a quarter. So it makes complete sense for this in preparation of startup production of MM.
They basically said this at the CC. They said they had enough money left to complete Mt Milligan, but they would have 0 cash and it would be very difficult to start up, and they may need to draw down the revolver at the last minute. This $350 million is a way for them to ensure they have lots of cash available, can hold off on selling moly if the market is low, etc.