Greentech's note mature in September. He was talking about now. As SLNN stands now, more than 200 million shares will be converted in the next few week. Not in September.
Also Greentech's notes is a "First Lien Note". It doesn't necessarily mean they think it will go up. It could also simply mean that they want access to certain assets in case of bankruptcy.
This provision that came with the terms of the note makes it even more likely: