Chapter 5 is when we really begin seeing two of the themes of Book 5. One of them is "movement": the journey itself is going to be (and remain) a large feature of the story. If you think back to the previous books in the series, there's not really a lot of movement going on:
Book 1: Yamato -> Jijinto
Book 2: Tonogasha -> Baron's Mansion
Book 3: Baron's Mansion -> Tanimura -> Shima
Book 4: Clanfields -> Hokusei
As far as the second theme goes...well, that's a secret! Also, don't worry about attunement too much--especially during early access. I'm still working the kinks out on how it's going to work. It's a bit different this time around!
Finally: I'm sorry about the delay with this month's side story! It's 12k words and counting, and since it's the 30th side story (and the last for a good while) I wanted to make sure I did it justice! You can expect it to come out a few days from now.
Book 5 Early Access: Chapter 5
(If the above link doesn't work, try this one. If that doesn't either, please send me a message!)