Put it down to an abundance of caution is my guess.. everybody (almost everybody) has high hopes for this stock, and not without reason. Selling means capitulation. Most shareholders apparently aren't ready to do that just yet, preferring to maintain the status quo and neither sell nor buy until more information/clarification is made available.
Just a continued 'wait and see', although 2m vol for the day is extremely low.. I think when it moves (either up or down) it's going to move fast, like it did a few months ago. Be ready.