Hi Lyle,
You will need a sleepover between Batemans Bay and Phillip Island; it's about 10 hrs without hitches, so too draining when you aren't familiar with conditions (and opposite side driving). Lakes Entrance, just under 5-1/2 hrs from BBay is a region of natural beauty, but is a little way off the main route you'll be taking, and your mission is to get to Phillip I. Orbost, a sizeable town on your route, is just over
4-1/2 hours, so a little under halfway. There is a range of reasonably-priced motels and hotels in Orbost. If you had the time, Eden is a wonderful stop: rich in history of the whaling industry and natural beauty. Sadly, if you desire only one stopover, it wouldn't be far enough along, and next day's trek to Phillip I would be too long. So, 1 stopover: Orbost. 2 stopovers: Eden, Lakes Entrance. Only my suggestions, and I'm sure others will have more advice for you.