About to book (using too many miles!) for next week F on our outbound and J on returning and never done this leg in F. Indifferent on the times as LAX’s two flights to LHR in the evening are within 1.5 hours. Can someone please let me know what’s the better call? Also, return in J I’ve done both but can’t recall what’s better. Appreciate the help!

Mods, was trying to search on my mobile but tough. Feel free to merge if available.