I think they needed to raise money at 1.8c in order to repay the...

I think they needed to raise money at 1.8c in order to repay the $7m loan that was due at the end of May.

I assume in the buyback they'll be moping up any weak sellers under 1.8c initially.

Yes, you're right it makes no sense to raise money at 1.8c and then immediately buy them back at a higher price - timing of cashflows and the recent share price fall to 1.3-1.5c may have also been factors in initiating the buyback.