My only relevant experience was in 2003 (so not very relevant), flying from JFK>LHR. I had bought some good Bordeaux at the then BBR duty free in T4 on the way out and going home I asked if my 32kg suitcase containing said Bordeaux could be taken on board as hand luggage. Check in said it was up to the gate, the gate said "of course". The CW passengers on disembarkation said "how the hell does that get allowed on as hand luggage".

My first and last experience of F.