Originally Posted by
japandigger
Is it possible to pay for the upgrade prior to getting to the Japan airport? i.e. calling JAL and asking/paying over the phone.
Or is it in person only on day of departure?
Better question for the JAL forum for the latest. In my recollection it's in-person, day-of-departure only. Usually it's a little sign with the offer on the checkin counter, although you can inquire whether or not you see the sign.