I thought N. baulus differed from N. secundiana by having a much larger white patch on the hindwing which shows on the underside , but is not evident in these photos
ok, it is N. secundiana going by the isolated (black above & below) small size white spot of the hindwing visable on several shots above. However, as Don said, on ALA N. secundiana is is listed as a synonym for N. baulus see https://bie.ala.org.au/species/https://biodiversity.org.au/afd/taxa/e78784a4-71a6-4749-b23a-53fd838ac9a6#names
For a long time Nyctemera secundiana T.P. Lucas, 1891 was considered a separate species. It is now considered a synonym of Nyctemera baulus (Boisduval, 1832).