Uh, so I never saw anything about this until I just realized it myself, but is there even enough Box space in-game to store one of every available Pokemon?

I was just formatting my Boxes by Kalos Dex order and I realized that the Central Dex alone barely fits into the in-game PC. What the fuck? Are there expansions that you can get? Because if not, then this makes Bank pretty much required for every collector and that's bullshit. I mean I'm gonna pay for it anyway to use Transfer but it doesn't even come out for two and a half months. Am I literally going to have to start releasing or giving away Pokemon in order to complete the Kalos Dex before Bank comes out!?