By BA marketing standards, it was a relatively humble and direct message. It's one step in the right direction towards a more authentic communications style that I've thought for years would better serve them (e.g. being more realistic and honest rather than pretending that everything they deliver is perfect).
I say one step in the right direction because "We have learned some lessons in this past year and where we have fallen short, we have listened and are putting things right." and "We look forward to choosing which destinations to fly them to, and we will let you know as soon as we can." were the type of messaging that feels reasonably authentic to me.
If there's one time a year when a company should send an email like this, it is now. BA have made quite a few legitimate improvements over the past year (far more than I think any of us expected 12 months ago), and it's worth highlighting those once in a while.