Originally Posted by FrancisA

I am not sure if it is the fare rules per se, but I suspect it is. UK availability of ex-EU originating LH flights is likely to be more restricted and I do not think that it covers the cheapest fare buckets, as I imagine that they are only available for sale from the EU country. So it could be not available in that market, rather than forbidden by a fare rule.

Whichever way round it is, ba.com will not book you into comparably priced ex-EU fares if you select upgrade using Avios. The UK-issued ticket will cost considerably more than the ex-EU issued ticket. If an agent can get round this, I would be interested in whether it is because they can actually issue the tickets in the UK at the EU price or whether this is some work around which is outside the either the fare rules or the BAEC rules.

It would be nice to have an official BA view on this. If this is legitimate, I would happily pay for my ex-EU CW tickets to be issued in the UK and MFU them to F. As far as I know, this is not possible at the ex-EU discounted CW price.