Don't think they have enough cash to cover that payment and have to raise some more to cover it.
Please correct me if I'm wrong, but I do think the number of outstanding shares plus warrants is close to 4ooM now. The max approved number of shares are 450M. So they can't raise that much more money by selling shares (and giving away "bonus" warrants) without getting more shares approved, which I think would require a shareholder vote.