[EDIT] Since this is garnering more attention than I thought it would: I would assume the NSUID update would line up with pre-orders as it has with other games, and pre-orders would likely line up with a Direct for TotK. I'm not sure it means one is super imminent - Nintendo could also just make a tweet. [/EDIT]
The Advance Wars 1+2 Reboot Camp and Tears of the Kingdom eShop web pages just popped changes with new NSUIDs attached to both (or, at least, on the Canadian eShop pages).
Credit goes to
lbabinz on Twitter for monitoring these pages for changes (he did not post about these changes, they're from a Discord chat).
Advance Wars:
Previously (Dec 2022):
Today:
Tears of the Kingdom
Previously (Dec 2022):
Today:
Tears of the Kingdom previously did not have a NSUID. It now having a NSUID means pre-orders will be going live at some point in the future, potentially in the near future.
I would think it's safe to assume pre-orders opening would line up with a Direct.