It appears to me that the B717 is being replaced by a bigger capacity aircraft. This will require more passengers to justify the aircraft and there are no prizes for guessing how and where they will come from.
The move could be part of a greater re-organisation within QF.
Without a big increase in the number of passengers flying and with the use of larger aircraft it is hard to see many new job opportunities for pilots in the near future.
Growth and expansion at DJ could slow down.