Can you change your 241 companion voucher Amex BA voucher flight for free?

[Crey]

Hi i have booked my flights from London city airport to Spain and a Heathrow flight has popped up can i change my flights for FREE OF CHARGE to the Heathrow seats that have come up on seat spy?

and can i do this online or does it have to be via the phone with BA?

[BJ]

It will only be FOC if you booked the original flight within the previous 24h otherwise you will be charged £35pp (or whatever cash you paid if less than £35pp). Check if you can change or cancel via MMB, if not you need to call.