This refit hasn't started yet so thebasource is unlikely to have details until a few months into 2018. For seatguru on past performance will be several years off, since they haven't put previous updates online yet. I think it is unlikely there will be a gap between 10 and 11, it's showing on BA,.com in order to keep rows aligned judging from other cases where this happens. I can't think of a reason to put a gap there and usually they are for exits or bulkheads, neither of which applies. And bulkheads can be good (WTP on 787-8s) or not so good (WT on 787-8s), we will need to wait for real world experiences. Row 10 may be available at T-48 by ringing up or at OLCI. But being LGW the chance of an equipment change between now and departure are quite high, since I assume this is for mid summer.