I don't have any first hand info on the subject, but I am with hilltopper on the notion that it would be strange not to have the superior F product on the longest routes.
However, LX and mothership LH are not exactly on a spending spree right now (unlike Etihad, say), so I can easily see how they would stretch the A340 refurbishment plans out for as long as possible. Keep in mind that replacing all C and F seats on such a bird is expensive, and the current seats haven't reachead end-of-life yet.