A few have asked when and how the DLC chapters are accessed.
As stated on the purchase page, DLC is accessed once the Astral Leyline is unlocked in the game.
In lore: The Astral Leyline is an interdimensional, inter-planar portal that gives the team access to all kinds of cross-over,
In game: I can use it to create new stories and new adventures with whoever or whatever I please and keep it in the canon of the story. Whenever you install a new DLC chapter it will show up in the DLC portal of the astral leyline. (Fire Emblem Awakening… the game that inspired Tactics Elemental… had a similar DLC portal location.)
I’m currently working on the next DLC chapter, and I have one more planned after this one.
I wish I could be more frequent with them, but once a year is the best I can do. Thank you for your patience.