It's alpha's intention to increase their position to over 20% so they will add more from current holding of ~16%. I would say it is perfect opportunity for them to add more at this point.
$ONCS Someone on Twitter, about the time Alpha took its second tranche, said it's possible Alpha could make money by shorting the pps. Maybe this is what's happening.
(I don't know if you remember or even saw the tweet I'm referring to.)