It looks like most (everyone?) was laid off, including David's Executive assistant (Carolynn Schmidtke). If you take a look at her linked in Profile ( https://www.linkedin.com/pub/carolynn-schmidtke/a4/786/129 ) she was at GAC until the beginning of this year.
In fact if you search for 'groen aeronautics' on linkedIn, you'll see a number of people that all are either looking for new jobs or have them as of this year.
I am speculating, but I think that there was a major 'bust up' between DG and the Chinese investors and they pulled out.
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