If I may,
I have a gut feeling it is China, and likely more than one customer, but on a limited production basis, basically where it will be a unit or two that are integrated into a scenario like a mining/shipping outfit, where they will basically give them a go and compare with existing technologies.
I have no proof of this whatsoever.
But my experience with other newer technologies, especially in direct competition with established large companies (take the welding world for example, with Miller and Lincoln... and out comes a Chinese-based company like Everlast, making smaller, lighter, powerful advanced TIG units that perform ridiculously well... I bought one and now recommend them to everyone), outfits will never order a number of "new-kid-on-the-block" units without picking up a single trial unit first. Compare, measure, conclude, and then order multiple units as budgets allow, and older units need replacing.
I agree GC is deliberate with his PR releases. But there may be other reasons for his being (clearly) vague that are in the best interests of the company, it's customers (sometimes customers doing a trial purchase prefer to keep it on the DL), and shareholders. It also allows for a healthy margin of error in case one customer backs out (which happens all the time, even on municipal levels, provincial/state levels, and bigger). It mitigates a potential over-reaction.
Just my 2c, I hope others weigh-in on your excellent questions/concerns too.
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