Option 21 Apr 2019, page-2

It's unlikely that the share price will fall to those levels again unless something drastic happens especially now that we are progressing quickly/well and with more good news to follow. The price is always dictated by the market and the market has factored in the options IMO. In addition, if all the options are exercised it will add $6.5mill to the kitty which will have a positive effect on share price as will the confidence of having them all exercised. I'm sure they will find any number of willing underwriters for the shortfall if people are silly enough to let them lapse.
As we get closer to production/DSO, the share price will only move one way IMO irrespective of options. (Up)
Good luck with your decision.