Earlier this week, it became possible to redeem JetBlue TrueBlue points for award seats on Japan Airlines, opening up potential sweet spots for traveling between the U.S. and Japan.While award availability in premium cabins for the first day or so the new functionality was live seemed to be limited to within a few days of departure and to business-class awards, it now looks like there is widespread availability of first-class awards and, to a lesser extent, business-class seats using JetBlue TrueBlue points over the next several months.As first...