It might be Acacia implexa, though that species usually flowers in summer in the ACT. The most reliable way of telling them apart is from the colour and shape of the fleshy aril attached to the seeds - white in Acacia implexa, red in Acacis melanoxylon.
The Acacia implexa nearby have more falcate phyllodes and do not yet have buds. Some A. melanoxylon nearby have tight buds and tangled seed pods sometimes with a seed showing red funicle. Originally I thought A. melanoxylon was uncommon enough on Isaacs Ridge that I should record each one, but as I discover more I am less fussy. A. implexa is the commonest local wattle so I record groups when they flower.