OP describes a type of deviation. One of few available techniques that can add a day to your life. Worth the effort, for sure.

I'm non- current, but in the past NRT has been tricky regarding how you get onto the correct Gen Dec and how your shorepass is handled. Also remember your call to C.S. to advise of deviation ( who would ever use sat comm???)

NRT d.h.deviations became a high profile issue in SEA a few years back and memos were produced. I'd suggest a call to SEA base ops for the latest gouge. They are on your side, and want it to work with zero repercussions. For actual on-scene assistance, a call to NRT "Inflight" can be very helpful (yes, that's a " thing" that scopes beyond flight attendants in NRT). If you're at the NRT Radisson earlier in your rotation, the hotel operator will make the connection for you. Having been the guy trying to explain the concept of " change of plans" to a Japanese immigration officer when the papers are not in order, I highly recommend the advanced leg work that you seem to be delving into. Good luck!