Originally Posted by
JJeffrey
And while a 6 hr overnight transit at HND is of course no problem I'm guessing the potential issue is that on separate reservations will JL see this as only JFK-HND and try to enforce any Japan covid entry requirements, etc. I would search/ask over on the JL and Japan forums as I'm sure this isn't the first time it's come up.
This won't be an issue as long as there's confirmed onward travel from Japan. JL or Japan itself doesn't care if it's on separate PNRs. Overnight transits are fine in HND (just not NRT) but unless the current rules change the traveler must remain airside during the transit.
-FlyerBeek