Newer 2017 LEAFs - made roughly after mid-July 2017 - already have this update from the factory. My car was made in late 2015 or very early 2016....so needed it.
my JDM November 2016 battery LEAF (first registered Japan mid December 2016) has the latest version of the firmware. Confirmed by GVI and Walter Larason.
So tech-savvy Japanese owners "in the know", via factory friends and the grapevine, could have been aware their near-new cars were possibly defective, and in need of remedial work, as early as January 2017. This might explain why last year so many bargains were available in the auction houses for export to conveniently distant New Zealand.