Perhaps two ways to see this : if a cancellation is notified at very short notice (day before ….. or even same day !), people get - understandably - very irritated because it messes with their plans / commitments and often with no time to sort workable alternatives. If - as in your case - the advance notice period is as much as three months, then at least there is a much better chance of rearranging things with minimal hassle. Not an easy call for BA.

I do however agree that it’s not exactly a good sign to be pulling flights this far into the future, when one might hope that a normal schedule can be maintained.