Originally Posted by
sscywong
Actually it's more than full fare difference
e.g. I know how much it takes to upgrade Y fare to J fare before flight (e.g. around HK$3,600 for HKG-PEK), but if you upgrade at airport or even onboard, it'll be north of HK$4000
Was on CX391 PEK - HKG last month and two pax in J wanted to upgrade to F onboard. I remember the ISM said the fare difference is like 6K-7K RMB. Which is crazy.