I had a discussion with an AIPA negotiator about A380 pay rates a couple of years back. He argued you always want to get the best conditions possible for a new type because it's going to be around a while.
I share you concerns Curtains.
I'm sure the smart people within AIPA are aware of this and just because the company may not want to change the conditions of existing fleets, doesn't mean AIPA won't suggest productivity improvements for the betterment of new type conditions.