Folks,
I would suggest it is being actioned with with all the sense of urgency and dispatch that is typical of aviation reform of any kind in Australia.
It has been going since the early days of RAPAC, probably 40+ years now, check in again in say, 2030, when the availability of avgas will be unlikely, so the problem will be solved, no further requirement, if, indeed, YSBK still exists.
After all, the significant piece of airspace that needs to change/shrink slightly is there to accommodate DC-4 freighter's (non)performance on a hot summer night.
Tootle pip!!