Not as far as I know. We took our son aged 5 months in with us in December when we flew LHR to JNB.
I'd suggest being aware of those around you and look for a quiet corner if you can. I'd also suggest booking a cabana as though they are underwhelming, they are handy for putting down a changing mat, changing clothes and sterilising bottles if you are using one of the water in a bag type arrangements.
Also handy if baby kicks off. Ours was very well behaved on the whole though. Thank goodness.
FYI, Boots sell Aptamil, but do not sell Hipp. We ordered it in but they lost it - we'd already given him aptamil the week before though and knew he'd be okay with it.
Once onboard, I found the BA First cabin crew very helpful and very proactive when it came to assisting us with the baby - so much so I put in a well done, as I was really impressed.