I think the recent volatility in POB caused this big shift. There were those who were hoping they could use their stake to censor on whim or were just expecting POB to continue to go up forever because it always had. When you have something that has been going up for a while, you attract the buy high, sell low crowd. They are the ones that see something going up and buy, but then they hold in anticipation of it going up some more, until finally the price of something goes down and then they decide to sell. They don't care about demand factors or limited supply.