If I remember rightly, isn't the area under a GDO, so they have no obligation to submit plans for alterations within the restrictions?
As others have said, I'd expect the area to close off so work can commence around Scarefest time, with an announcement being made to explain the closeure to guests. Also, by doing it within season it gives them chance to get some easy exposure and advertising to bring people back next year (Much as they did with Smiler banners and the logo appearing all over the place).