BBY are the brokers buying the shares for CDU under the buyback arrangement. So it looks certain that part of the move in the sp was CDU buying its own shares. Like 30% of turnover yesterday, 40% on Wednesday and 56% on Tuesday.
It's just the CDU way, buy at $3.25 and resell to new investors at $3.60. Dunno how they do it, but you've got to admit it's brilliant!