A few times I've been asked via auto check in kiosks, or via announcement at the gate if I wish to check my cabin bag. Last time at T5 I noticed there was a dedicated desk airside for this as well. Is this a standard offering, or does it depend how busy the flight is? I have an upcoming HBO flight and I'd be tempted to do it, but I would have thought BA would not want to encourage people to buy HBO and then check a case anyway. Anyone got any insights?