OOS online as of 3pm EST. Should be in store as well.
Please note that the weekly ad this week incorrectly has the full game (Xenoblade Chronicles 2) as $19.99 (it is actually $49.99). It might be able to be price matched at Target customer service or perhaps another retailer that does price matches.
Edit: Looks like Target may have corrected the online ad for the main game for $19.99. Still, the expansion at $19.99 is a great deal.