Q: Does cancelling my BA American Express card mean I will lose the voucher? Does downgrading my BA American Express Premium Plus card to the Classic card mean I will lose my voucher?
A: No. Contrary to what American Express will tell you, you will keep the voucher if you cancel the card entirely, and similarly your voucher will retain its two year validity if you downgrade from the Premium Plus card to the Classic Card. Remember though that you will need to pay the taxes and fees on an American Express card, so it may be worth asking to downgrade the Premium Plus to the Classic card for this purpose if you don’t hold another Amex.