Originally Posted by
Paralytic
You can't do it only - you have to phone up. Just pay the Avios and any change in charges/taxes. You'll probably also be charged an offline fee, but ask them to waive it since you couldn't make the change online.
We just used avios to upgrade our CW return from NRT to F and had to call up; the Agent on the Gold line charged us 2x £35 change fees. Should we have not been charged this?