Originally Posted by
IstKong
It is booked in economy light. If I change the return flight to economy flex by paying the 80€ extra will I be able to get a full refund (cash or voucher) on the return flight ?
No; you cannot do this. Do not pay extra money; you won't get it back.
Just think about it; if it was really that easy to "force" the airline to give you your money back, then there would be little point in the airline having different ticket families from the start.