There's a new sourcebook re courts and fortresses - https://www.fantasyflightgames.com/en/news/2019/3/1/courts-of-stone/
Perhaps more significantly, is the new adventure coming out; Winter's embrace - https://www.fantasyflightgames.com/en/news/2019/3/1/winters-embrace/
It'll be interesting how this ties up to the main storyline.
- Winter Court is at Kyuden Doji.
- Someone done officially invited Yoritomo.
- I can think of no way at all this could possibly end badly for anyone.