This latest datamine of upcoming software for the Switch's eShop shows a 12th June release date for the title (as already expected) along with all the information you'd expect to see including the game's publisher, genre, and a file size of just over 2 GB.
There is also mention of add-on content for the game with in-game V-Bucks and a Wingman Starter Pack theoretically being up for offer.
It certainly seems plausible, and it sits in very nicely with the already existing rumours. As always, though, make sure to remain slightly hesitant in case the reveal doesn't happen tomorrow.
Do you expect Fortnite to launch for Switch tomorrow?