I understand this looks bullish on havelock as such large buys are very rare indeed.

However, those were likely the same shares that were also on offer on mpex (190,000) last week for 0.0028 and got lowered a few days ago to 0.0025, then likely the one that had bid open for 300,000 shares at 0.0020 snatched them as his bid has been removed. Since on mpex there have been around 5 blocks of 1 million shares traded the past month this is not an exceptional large trade.  

I am surprised though that there are hardly any shares for sale at mpex. That's never been the case to my knowledge and might push the price upwards.

Though it all depends on the results of sdice also ofcourse.