I guess it'll just be one special per Doctor working our way towards November.
BTW, I finally kicked back yesterday afternoon and watched "The Aztecs". I watched the retrospective "prologue" when it was broadcast, but since the story itself would play until midnight, I recorded it show I could enjoy the presentation at a more reasonable hour.
Without revealing any "spoilers", I had to chuckle at the "byline" displayed at the bottom of the screen "You are watching a classic episode of Doctor Who" just to prevent any confusion for the casual viewer. "Honey, the TV's on the fritz! It's lost the color and the clarity!"