Then they stated that going forward, 'Big DLCs' (as distinct from Race Packs) would contain a new race and four legendary lords. In the blog, they described the early adopter bonuse for TW2 (which turned out to be Norsca) as a Race Pack, and said it would be in line with the Chaos Warriors Race Pack or Bretonnia in terms of content.
In July 2017, CA published a blog regarding early-adopter bonuses and DLC for Total War: Warhammer II.
Originally these had mini-campaigns included with them, but going forward they will no longer have mini-campaigns, and will instead have more legendary lords, features and polish. Creative Assembly released a blog post detailing the types of DLC that would be available for Total War: Warhammer.