Pretty sure it's upon receipt, although the "material event" may have been the announcement of the WNEC deal. So it seems odd to me that there hasn't already been an 8-K.
I've been doing a lot of digging around about this, and can't find a clear answer. Companies appear to have some discretion in determining what requires an 8-K. One possibility is that they didn't deem the amount received as significant enough to file an 8-K.
But there are many exceptions to filing rules outlined in the instructions for filling out the 8-K. A couple appear to possibly apply to this situation, but I can't tell for certain. Maybe ShadowSpy69 can weigh in? See more at https://www.sec.gov/files/form8-k.pdf
Definitely adds a little more mystery to the upcoming 10-K.
As for your list of potential positive news, I think only a new licensee would move the needle, and possibly the right kind of DOE news. I suppose if there were a genuine big name investor, that could provide a bump, too. Plant location, not so much.
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