Newbie,
I don't think you're right. Both Balpa and AOA have taken advice on the Age Discrimination Legislation and despite it possibly having to go to court in a test case it seems to hold good. BA have immediately changed their contractual retirement age so they didn't think they would win.
In France Ryanair and Easyjet have had a court rule that they must follow local employment laws.
HKG hasn't yet got this legislation so I suppose you could have a retirement age of 55 for HKG based pilots and 65 for based ones!! That would cause some havoc,