Ah, JL. A word of caution. The cabin tends to be extremely hot (apart from in F, where it's much easier to talk them into lowering the temperature anyway).
Have a look at the JL forum for a thread about the hot cabin.

I always come off JL flights feeling absolutely dreadful because of the cabin temperature being set too high. It stops me from sleeping and it makes me feel like I have a fever because it's so hot. I have been told by JL cabin crew that setting 24-25 degrees in the cabin is their company policy because a lot of their passengers find it otherwise cold. The crew thought it was too high too, incidentally, but it's the company policy so she couldn't deviate from it. I do notice a lot of Japanese passengers have a jacket or cardigan on even at that temperature.

There used to be lots of complaints on this forum about BA when the cabin temperature was set even at 22 degrees on overnight flights. So, think carefully about this 24-25 degrees business...

I thought you were thinking of BA 8!