Why not go out F and back J, if you are not miles rich ?

The longer "day" flight outbound allows plenty of time to sample all the F goodies, rather than on the return when a lot of time will be spent sleeping in what is one of the better airline flat beds.

Only downside is I don't think from threads this week that you can book a different class 241 online, so you'll be hit the 15 quid phone booking charge. Have a read through this thread to confirm.