I recall him saying that too! Don't remember where he said it tho.
EDIT: I found it! It was in the Ultimania!
Nomura: At this point in time, I have given the staff a list of the battle elements I want to do, and they are investigating. As for additional story, I think it will mainly be expanding on the Keyblade Graveyard things I mentioned before when I talked about narrowing my aim. I do plan to complete it as soon as possible, but as we are working on it alongside preparation for the next project, I still can't tell you when to expect it to be released. For the time being, we are planning to present several pieces of content as one pack rather than release several separate things.
Me thinks preparation means Pre-Production.