An announcement about closing, new attraction, reopening date, and all of that sort of stuff that typically would be overhyped twelve times over are a catalyst for a reaction to which Disney has no good answer. Waiting means they can wait until it is too late and in the mean time play dumb.
Yes, and they also love spending millions of dollars flying in Mommy bloggers and Lifestylers for an event where they can hype numerous things (like say the 'new' rooms at the BWI and even new menus at certain locales). Ultimately, that's when it will be announced, even if construction work has already begun.
All you have to do is find out when the next major 'media event' at WDW is being held ... then you'll have your answer.