I booked a W class fare from London to Sydney which I would like to change. Quite happy to upgrade the fare class to a Q or H ticket and pay almost the same again if necessary.

Spoke to United in the UK and all seemed fine when I enquired about other fare codes to understand how much the difference would be. However I have now been told that I can't change the W class fare at all. This has been double checked and the second CR agent I spoke to said it was news to him and he hadn't come across it in his 3 years there before.

Does anyone else know if this is a new condition on W fare tickets. I was told that the important line which talks about upgrading far codes provided the flight costs more has been removed on my ticket and thus possibly other W fares?

Should I contact Customer Relations in the US as I always thought you could buy-up on any fare codes?

Thanks