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When I come back from Vietnam to North America, I have an airplane transfer in Japan. The arrival time is 6:55 AM in Haneda airport and my second plane is set at 11:10 AM the same morning... (gives me a small total of 4 hours and 15 minutes to get from the first one to the second one).
I read that it takes about 90 minutes with the airport bus system, but that it could take much longer because of traffic (and that I could wait some time before the bus departs).
It is possible? What is my alternative if this doesn't seem doable? Call my flight agency and change it?