https://wccftech.com/mario-kart-8-deluxe-new-leak-reveals-unannounced-dlc-courses-cups/

Mario Kart 8 Deluxe has just received the first eight new courses that are part of the Booster Course Pass, and the new patch's files include information on yet to be announced courses and cups.

As reported on Twitter by @MrNantendo, a Mario Kart 8 Deluxe banner that has been discovered in the game's files features images of yet to be announced tracks. Among them are Syndney Sprint and LA Laps from Mario Kart Tour, Mario Circuit and Vanilla Lake from Super Mario Kart, Koopa Cape and Maple Treeway from Mario Kart Wii, and others.