On Saturday I saw 2 bees at the same time almost feeding on the same flower and after reading Fronds articular at https://friendsanbg.org.au/sites/default/files/pdf/News86Aug17.pdf the plant must have been the same Acronychia littoralis.
This must be the most photographed insect at the moment! As various recorders have suggested there appears to be only one individual involved. The flowers belong to Acronychia littoralis from littoral rainforest in NE NSW
After seeing 2 bees together at the same time on Saturday I went back today and can firstly confirm Acronychia littoralis, but after spending several hours watching I did not see a single one of these bees. They might be carving new holes but no sightings at all.