Yes, please do complain - as noted, make it short, concise, unemotional. Service recovery seems to be a little more generous recently, and even if you have no interest in that they might at least update their information.

viz, it may be likely to be a sleeper service, but it is not currently listed as one: https://www.britishairways.com/trave...e/public/en_gb (only the LHR route is)