Originally Posted by
Often1
If you are flying to the US, bear in mind that DHS rules prohibit passenger movement between cabins. Officially that means a Y pax can't walk up to F. But, that is honored in the breach by crew. So, make certain that you ask. It would be rare for a BA crew to deny the request.
AFAIK this applies to flights TO the USA, not from JFK to England which seems to the the OP's route.