I don't see them doing something like this unless they do severely jumble around their content cycle (e.g. delay tome gear, delay crafted gear), seeing as delaying it can have consequences in other areas of the game. Namely crafting, if the tier is delayed, the need/desire for crafted gear immediately goes down, and by the time the raid patch does come out, the gear will not even be worth half as much as it currently is, since the need for it isn't really imminent for anyone.