Originally Posted by
Ronlap
I upgraded from K on FRA-BLR for $275 but could not upgrade from U on the return. Hmmm...
NewbieRunner referred to mileage upgrades.
For cash upgrades at a fixed price, all paid fares are eligible, see
http://www.lufthansa.com/us/en/Upgra...-Economy-Class
I guess premium economy premium class N is not available at this time for your return flight and you can't cash-upgrade.