Ain't it all fun.
Yes, it is!
For the record, the last time I saw a Utility was in the early 1980s, in the hands of a chap called Fred Delfine (?), but that was a Utility-JAP. He lived up in the Dandenongs somewhere, and was burnt out in the bushfires. I don't know if that Utility survived, but I'm sure they're around, possibly not identified.
But back to Alex's dad's Villiers. Of course we're not guaranteed that it's in original condition in the photos, but some of the identifying points would be:
1. The heavily valanced front guard, and the heavily valanced front half of the rear guard
2. No rear axle stand visible, so it probably had a centre stand
3. The headlamp with ammeter and switch
4. The gear change gate up high on the tank, with a lever that looks straight-ish beyond the pivot
5. One-piece pressed steel tail-light and number-plate mount
6. Squarish-looking stuff under the saddle (battery/toolbox) where the round autolube tank goes on the vintage models
Anyway, I reckon most of this stuff adds up to late 1930s James, but I'm way short of an expert on such things. That tank has me a bit mystified - maybe they had some old ones to get rid of on the "colonial model"? I don't suppose Waratah bought a batch of bikes from James?
Cheers
Leon