I have a changeable booking in economy and was playing around with some dates and noticed that I could change a flight to another date with the same fare but higher booking class and just pay the booking fee (in my case just 50 EUR), so in theory I could upgrade a V-class ticket to an S-class (double miles, fully refundable). It didn't make sense but this is what the website showed so I decided to go for it. Well, 50 euro later I have almost the same flights in the same booking class (V), basically wasting my money.



Anybody has an idea why and how that happened? I would expect to pay fare difference and not just the change fee. Funnily enough, if I try to change the flight to the same flight (website allows that as well), then the change goes ahead without payment, I get my tickets reissued and again - booking class is the same as original. Am I missing something here?