Was the deal on? An offer was made by all accounts and according to PCP it still remains on the table - the issue appears to be that Ashley is asking for more money and or a reported clause linked to relegation to be removed.
The whole relegation thing is what's complicating the deal. While there's a doubt over Newcastle's survival PCP won't pay the value as if Newcastle are an established PL side, equally Ashley will hope that if they stay up then he'll be able to get that extra money. Ashley's rolling the dice in the hope you stay up and he gets his price in the summer and if history is anything to go by then even if you go down, he'll hold on and try to get you promoted again to get that price then.