On Wattpad, where I'm uploading the book, readers skew young. The stats say 30% of my readers are under 18, 30% are 18-25, 30% are unspecified, and the remaining 10% are 25+. YA, of course, is read as eagerly by adults as by teens, but the expectations are the same: as a publishing genre, YA by definition deals with teen concerns.
The Wynter Wild series isn't YA. Three of my POV characters are adults, but the New Adult label doesn't fit either because (1) they are male, and (2) their stories aren't romances. I used to refer to the series as a Family Saga although it only covers a few years. An author who rated the series on Goodreads called it "New Adult Family Saga" and I like that... but it's not a genre that publishers recognize. (Publishers need to know where to "shelve" a book and a random crossover is a hard sell.)
In addition to publishing genres, there are Wattpad genres - not only main categories such as General Fiction (where I put this series) and Teen Fiction, but also tags by which readers can search for what they like. My series has certain tags for visibility, such as teen and cult and music, as well as the popular "little sister/older brothers"-type tags (a subgenre I never knew existed when I wrote the series). This subgenre comes with expectations of its own that I can't fulfill...