I was just having a read through the MAM EBA, talks nothing about restrictions on aircraft types, just says that you will be trained to the same standard that the client airline mandates.
So as I see it, QF just has to contract MAM to provide support to Long Haul, and bingo. And the Long Haul EBA 7 does allow casuals, with many of the same clauses that the short haul EBA has, and appears to be breaking.
JB