The thing with BAEC is knowing when your Tier Point year runs - a calendar year is much easier to track than a year that ends (in my case today).
However, I will reach EXP tomorrow and I am very tempted to accrue BAEC points on my December flight (215 Tier points for one round trip).
The question I have, like someone else is whether I can use my EXP benefits next year if I am crediting to BAEC? Most of my flights are TATL on BA and AA (with connecting domestic flights on AA of course).