Originally Posted by BAHumbug

You can ignore my subsequent brainwave as I realised you'd be stung for the UK APD which is what you're trying to avoid.

The rule is that any connection which is <24 hours is a connection and not a stopover so APD is not chargeable. The booking engine is pushing out the wrong fee but I can't think of any other way of making it work. Multi-city would do the job, but that only works for non-redemption bookings.

I do think you'll need to call I'm afraid. I think you should argue the offline booking fee is waived, because the stopover part of the BA website is churning out incorrect fees/surcharges.

BAH