You can use semantics all you want, but the smaller team in pre-production is used to develop the concepts you saw at the presentation. Pre-production is about nailing the game mechanics, the look of the world, the characters' final designs and the story, etc. Production of assets and the full game come in the 'full production' stage you mention, but that also includes time to iron out bugs. Saying that 'full production' began in August doesn't change how tight the schedule is, especially since it appears they are recycling less, and introducing many new mechanics and a new world.