I agree that WDW should do a better job at their medium range calendar. At times, posting times for fireworks for a particular month just two weeks before that month is indicative of some sort of dysfunction.
But... c'mon, folks. WDW has been doing this pretty consistently for the past three years that I've been keeping track. On Reddit, blogs, and forums there is a regular cry of WDW doing away with EMH, or Wishes, or a night time parade, or closing ridiculously early, or doing away with a new show simply because their official calendar doesn't have it scheduled three months from now. Wait six weeks... and behold, it's now on the calendar!
Yeah, that sucks and WDW should do better, but... really shouldn't be a surprise since it happens all the time.