Originally Posted by
Sheun
My understanding is that Airside departure is closed overnight. So what time do they re-open in the morning? Would there even be airside transfer security staff at this early hour? Or should I expect to clear immigration and wait landside until they open airside departure?
I don't know for sure, but I expect the transit immigration and security checkpoints open in time for the first arrivals. If those checkpoints were not staffed, then some people would be forced to wait airside (e.g. people who don't have permission to enter Japan). I have never heard of such a thing and I don't think there's any seating for people near the entrance of those checkpoints. All of which suggests to me that they're open from the time of the first arrivals.
I have heard that the airside, inter-terminal buses don't start running until later in the morning, so people who arrive very early and need to make a cross-terminal connection end up waiting in the terminal where they arrived - an annoyance for folks who have lounge access in the other terminal ... However, your connection does not involve a change of terminals so this should not affect you.