Specifically, it will be available at the following times:
- Evening of June 13 (United States)
- Morning of June 14 (Europe)
- Morning of June 14 (Japan)
- Afternoon of June 14 (Australia and New Zealand)
Here is an overview of the expansion, via Nintendo.com:
Play as an Octoling in a new single-player DLC adventure with 80+ missions!
Play as an Octoling for the very first time in this large-scale downloadable content for the Splatoon 2 game! This full-on single-player adventure spans 80+ missions starring Agent 8, a new character who awakens on a dark subway platform. Navigate this mysterious underground test facility in a desperate battle to reach the surface of Inkopolis. Escape from these twisted depths, and you’ll finally be able to join multiplayer* matches as an Octoling!
You may think you know everything about the world of Splatoon, but these waters run deep, and so does the lore. Purchase this content today for immediate access to special octo-themed in-game gear.
- Play as an Octoling in a new single-player adventure spanning 80+ missions
- After waking up without your memories, navigate an underground facility to reach the surface of Inkopolis
- Take on a variety of mission types packed with new challenges you won’t find in the main game
- Complete the campaign to unlock Octolings (Girl or Boy) as playable characters in multiplayer* battles
- Clear additional challenges to unlock more than 10 new pieces of in-game gear
- Purchase this DLC for immediate access to octo-themed in-game gear (Studio Octophones & Octo Layered LS)
Additionally, while Splatoon 2 content updates were previously scheduled to end in July, Nintendo announced that it will continue updating the game through the end of 2018.
Watch the launch trailer below. View a new set of screenshots at the gallery.