justanoldboy,
The problem has arisen because the A330 wasn't around in 1992. It is a new type and originally started doing some SH flying.
Now it is primarily LH the SH blokes want to maintain their bidding status and use the vagaries of the agreement to shoehorn their way to the front of the queue....or as close to it as they can spiv it.
It gets really interesting if the 744 starts to go to the scrapheap. 744 blokes, now sitting fat dumb and happy that they have finally "made it" may find themselves assigned to the A330. Changing to a bus at this stage of career may not be a real attractive proposition to some. Being junior to an opportunist would make it very unpalatable indeed! Salt to the wound so to speak.
If the SH proposal to nuke the LH blokes gets up then it could get very frosty in the crewroom. Not that it would worry them.