You are correct that there is no concrete evidence, but look at what happened in December when AMBS changed its CUSIP number and name. Our German friends told me this forced the MMs on the BBSE to temporarily delist the company when it went into effect, and when that happened the PPS surged.
Association is not causation. I remember that last Dec was also rife with anticipation on the part of AMBS shareholders over the impending Jan Bio confernece, more MANF study data and a lot of optimism over a potential MJFF grant, as well as a lot of hope for other 'catalysts'.