Three of these caterpillars were seen, blending in with the sprigs of wattle they were on. When disturbed, they dropped their heads down into the wattle to reveal eye spot markings and a stripe on the rear of the head structure.
Possibly this wedge moth species which has been similarly photographed on wattle in the ACT, see https://bie.ala.org.au/species/urn:lsid:biodiversity.org.au:afd.taxon:ae16d838-c09f-4fdb-8bfa-242b69963494#gallery