Originally Posted by
LH4116
If I want to use my vouchers to upgrade a ticket ex-LHR, so I have to pay any additional APD tax?
I'm leaping in to give a late answer to this, because it originally received one that might have been unintentionally misleading.
Upgrade an UK-origin, APD liable flight using any instrument, miles, or vouchers and you (or more correctly, the airline) must pay the higher level of APD. An upgrade required for operational reasons escapes this.
Of course, the airline doesn't have to pass the charge on to the passenger (through goodwill, or ignorance), but I'm pretty sure most will do so.
Upgrading my LHR-IST-KUL trip would cost me over £70. Upgrading just the IST-KUL bit costs only the miles....