I too am puzzled by the rapid run up of share price. But I was thinking that perhaps it was the buyback they have had on the books for quite some time. It's a great way for insiders to increase their ownership of the company without triggering insider trading criticism, as it benefits all shareholders equally.
With the company turning around, I wouldn't be surprised at all if they pumped $100-150 million buying back stock.
Also, it's a great strategy for management to do if they planned on taking the company private, as it just increases and concentrates their already overwhelming ownership.