If you go 34000 blocks high, then you get the "Great view from up here" Advancement

So I was building a tnt blaster that blasts you into the sky in survival, and managed to get to a limit where it bounces me off a wall or something like that(y coords: 33432). But out of curiosity, I flew with my elytra up a couple hundred blocks(y coords: 34001.3). And after a 1 second delay, I got the "Great view from up here" advancement.