I find it very hard to believe that they (the BBC) have just noticed this ... maybe they are responding to a press-release by the BAA? However, the demolition has been going-on for the last few months (6 months?) at least.
As I drive around airside, on my irregular trips around the 'roundabout' above the entrance to the cargo tunnel, you can see that they have already demolished one of the piers, and they had already almost completed the next pier along.