If you submitted the complaint on Saturday 9 November (per your reference to "yesterday" as 8 November) you will not be getting a response for a little while yet. Response times are weeks or months, not days.

This all sounds bad but is there a reason why you can't just rebook the "cancelled" November trip yourself, rather than asking them to reinstate it? Have you been charged? Given the timelines associated with complaints, it's unlikely that they look into it and conclude on what to do with enough time before any November departure date.

That phone number might be the old duty office, and I agree it doesn't work, but contact numbers for BA Holidays are available here: https://www.britishairways.com/conte...cts/contact-us

"Despair and anguish" seems slightly OTT I have to say, as well as a booking/IT mix-up and unhelpful call centre staff ruining your passion for travel forever more - whilst this undoubtedly feels like a real annoyance, that kind of thing in a complaints email doesn't generally help in having it taken seriously and won't get things resolved faster. I would suggest if you have to write to them again to take out the emotive language and stick to just the facts. I do hope you can rebook and enjoy your trip, Athens in November should be lovely.