AY no longer operates the cheap flights.
JAL has recently released a domestic First Class on selected routes.
Given JAL also has domestic business "Class J" - am assuming the new First Cllass will book into a First Class earning Cat.
Latest routes here:
http://au.biz.yahoo.com/080327/44/1o70k.html
Description:
http://press.jal.co.jp/en/release/200701/000661.html
Upgrade from an economy ticket is Y8000 ?(A$83) (US$77)