Hello Hiro-san,
At https://wwff.co/awards/national-programs/ the JAFF coordinator is JA1JCF (nb-hyaku@nifty.com) and the JAFF log manager is JI2SVL (jaff-log@nifty.com). The JAFF website link seems to be outdated, though, and I’m not sure if there is a more recent one.
73
Kim OH6KZP