Hi all... is it a known ba.com bug that the 'upgrade an existing booking' button just takes you through to 'manage my booking' with no explanation if no award inventory is available in the MFU booking class you want, or if your base fare class is not upgradeable?

I have an I class CW LHR-HKG booking in early June which I'd like to MFU to F on one or both legs, but I'm not being given any clear information by ba.com when I try... just ending up in 'manage my booking'

TA!