From 1st September the Tokyo to Sydney route with Japan Airlines will feature the first class JAL Suite. You can book it right now for 103000 Avios and £210. For reference, business class on that flight is 77250 Avios + £118.
Given that there are just 8 seats in first class on the JAL 777 this will be quite an exclusive ride.
How to book Japan Airlines with Avios
JAL award flights can be booked with Avios directly at British Airways. There is lots of availability, with 2 seats available on many dates.
This flight would mean nine and half hours in first class. JAL also has first class between Tokyo and London, Paris, and New York.