Really cool how you combined the two mechanics. The change of pace between the two game-plays is really interesting, and the game is really polish for a 48h game jam. Good job.
I do have some comments though. The two enemy's bullet types can a little bit hard to distinguish. And the differences between the movement of the bullets (smooth) and the blocks (snap to grid) is a little bit confusing.
Goodluck with your game :))