JAL rosters
Rostering is done at LHR - up to 90 hours p/mth, get it around 25th and there's no bidding, swapping or negotiating. Includes SBY and reserve days as well as Jpnz lessons and any compulsory courses like SEP or crew meetings.
Shortest trip 3 days D/H LHR-NRT, arv next afternoon min rest n/s, work back NRT/KIX-LHR
4 day trips LHR - NRT/KIX/NGO, n/s 2 nts, back
5 day trips d/h LHR - CDG/AMS KIX/NRT/NGO n/s, 2 nts, and back - have to d/h back to london the same evening
6 day trips through MXP or FCO
9 day trips to SYD and DEL (not sure what's happening with that because they share with Frankfurt base)
No per diems/allowances up front it's all calculated in arrears and they are fixed per country, if I remember it was calculated in USD and converted but as you are aware $2 to £1. If you do duty free there's no comission given to the london crew, you do however get a flight allowance for the direct flights and a slightly higher for the flights where you go through Europe.
They have cut the basic over the years by 10-15%, couldn't tell you how good or bad it is now.
If you don't fly you will only get your basic. Pretty standard stuff.