For anyone else wondering about the update, here is the changelog from steam:

Hey everyone!

Yoku's Island Express has just launched a new game mode: Randomize!

This mode will allow players to explore the world of Yoku’s Island Express, but this time the order of all the unlocks are randomized.

Please note that NPC dialog is unchanged and might refer to items you’ve not received. Finishing the main game first is strongly recommended!