More interesting, BBC says the original work shows a lady looking at an empty plinth, she's not looking at an empty plinth in my view, she's looking at the grey paint which has been elevated on a pedestal. Am I wrong? Were the big grey rollered patches painted there by Banksy? I think there are others on that wall that are not part of this picture, I'm sure that's how it looked when I was there... Can't go back for another investigate this weekend as I'm busy.
UPDATE: Of course the banksy is now gone from Folkestone :-(