Originally Posted by
asya999
I'm going to try upgrading C->F SFO-MUC and back in June, but I'm curious: whom do you call ahead and what do you ask them? Do you call LH at the airport you'll be upgrading from or central LH number or what?
You may have some problems upgrading C->F on those flights. (They're operated by 2-class A340s, ie no F.

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