I don't envy you BTW, just learnt on the BA forum that regularly, when Y is not full, cabin crew come to speak to W passengers and tell them that if they want, they might be more comfortable moving to Y where they will secure them a full row for themselves! At first it sounded weird to offer a downgrade, but having both traveled in W (both AF and BA which are both rubbish in that particular class I would say unlike TK, NZ or QF) and in Y with a full row to myself, the latter definitely is far more comfortable and I would give the BA crew a ^ for the initiative and for securing a full row to the W passengers in such a case.