Quick Bravo over dismissing Australia (5,2)
I believe the answer is:
hurry up
'quick' is the definition.
'bravo over dismissing australia' is the wordplay.
I cannot quite understand how this works, but
'over' could be 'up' (e.g. if your time is up it is over) and 'up' is present in the answer.
The remaining letters 'hurry' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for hurry up that I've seen before include "Run" , "Make haste" , "Be quick" , "Get a move on!" .)