I think the sudden change of controls would've been nicer if every time there was a popping up text/image that signals about the need to look at what are the controls now. Also, I think adding more time before the change will be good, because it was way too short for playing normally.
But apart from that, the game was fun and well done for 48 hours. Instructions were clear and intuitive. With some polish, the game can become even better, but it's good overall!