Personally, I think it reasonable to expect most people to have made new plans to travel within the November cut off date
Some people have a 'family &/or friends' annual reunion for birthdays or whatever. It is the same time every year. They missed this year's get together in May/June; travelling before November is of no use to them at all. Equally there are some destinations where the weather, the wonders of nature, the festivals, the 'whatever it was you were going for' is only applicable in May/June. That is what you wanted and paid for and that is what you missed. You will be doing the same next year and deserve a free ticket for what you missed this year. That is a perfectly reasonable expectation.
The more unreasonable;e BA make this the more hurt they will do themselves. I suspect the aftermath of this will be very public in UK. They need very careful, delicate and utterly white as snow
PR.