The dimensions of this year's series of phones will NOT change in any way that would require retooling their manufacturing plants. A slightly thicker screen is no big deal to adjust to, but there is no way they would be making a bunch of new dies and tools for an odd-year release. That would cost just as much a retooling for a whole new design, but not nearly that many people will buy it because it basically looks the same, so it's not worth the investment.