The Global Volcanism Program has a brief overview of the Newer Volcanics Province (NVP for short). Overall there has been volcanic activity in this area for the past 60 million years, the NVP is associated with the volcanism in the area over the past 5 million years and hence has been termed the 'Newer Volcanics'. The area in question spreads over 15,000 km2 of central and western Victoria, and is an excellent example of intra-plate volcanism as many of the volcanic formations left behind are still visible today. Overall there are around 400 volcanic vents and shield volcanoes. They can generally be described as monogenetic in nature, which means that these volcanoes are only active from the same vent once.

Study in this area has not been extensive but enough has been done to understand the nature of the volcanic field and the hazards it prevents. One thing is for certain, as has been stated in other blogs (listed above), using the word overdue in volcanology is not good practice, and is a bit like a train in the UK, you never really know when it will turn up!
Sources
Matchan and Phillips, 2011. New 40Ar/39Ar ages for selected young (<1 Ma) basalt flows of the Newer Volcanic Province, southeastern Australia. Quaternary Geochronology 6 (3-4), pp. 356-368
Global Volcanism Program