Is there much first class product from London to these relatively close Euro cities?Husband is going to Denmark (Billund ) for a day lol
Basically that is the reason for the trip
He likes to try out other first class airlines for a sticky beak.
Probable Paris or any of the German ... Austrian cities
You could go via HKG, NRT, HEL, DOH or MAD using OneWorld
Going anywhere else is a challenge as you have the one stopover rule in London
Can you stop at Billund on the way over, or does it have to be mid-trip?