Who knows.
But I doubt the RAAF would have done so without a nod from the USAF - right?
As someone said earlier, for deterrence to be effective it needs to be publicised (to a degree, sensibly, taking into account Operational Security).
Quite happy to be corrected as a civilian, but I would have thought any operational security implications here are reasonably limited?
So in this case - what might be the message that is being sent - and to whom?
In the case of the USAF, its message might be "...we have friends who will not hesitate to actively assist us and are doing so, despite any overt or veiled threats to them..." and I'd suggest it's a message as much to China as anyone.
I would suggest flying your most valuable strategic bomber on the way to an actual real mission through a staging point like Tindal is a big message to send.