If it is indeed the QR J seat then much obliged. While the foot-well is on the small side, I can lie down flat without my squishing my feet, unlike the CW seat (unless in exit rows). 6'2" 85kg size.
Row 1 hopefully blocked for Golds, as that foot well is three times the size.
AY J is a bit cramped on the 350, as posted above, and that would be a blunder by BA if installed.