It was always planned that pier 3 was where domestics would connect to the dedicated domestics arrival route.
When pier 3 got "postponed" the biometric solution was chosen, when the issues were identified the new solution under construction is basically a hybrid of what was originally planned minus the attached pier.
My understanding is that the forthcoming domestic bus drop off point merely links to what would have been the pier 3 route and so hopefully at some point the pier will be attached.
Its fair to say MAG have taken the issue and the feedback seriously by building this hybrid solution, and absorbing bussing costs until pier 3 can be justified.
Taxi times are a work in progress with the remote stand capacity urgently needed and both these and the dual taxiway works both need the old sheds gone so its likely we see an announcement on this before too long.
Any notion of domestics going back to T3 are just fantasy, the 2 terminals have clearly defined roles finally and thats been a long time in the planning