Quote:
Rod, would you have a name or names for a Postmark book that includes the KGV era? KGV.
Aaaaah! my friend, please do not open that particular can of worms.
You'll sink under the morass of infinite variety.
This is for stamp collectors who have no hope left,
they have submitted to infinity, even as a "world wide" collector
I look upon the postmark collector as a lost cause

You have (in Australia) several methods, but if you insist, I would advise you in collecting postmarks of your particular state.
There are Ronoed A4 compendiums of postmarks of each state, and they are whoppers.
I have mine of Western Australia, and it is cased in a glass box
in the garage, with a hammer next to it, it states..
"Break Glass in case of boredom"
I have yet to meddle with that horror, it's expensive too!
I have "The Slogan Postmarks of Western Australia" by Brian Whittaker, a member of our stamp club, it's a beauty
but that's only slogans

To grant your wish, you would have to secure all the compendiums, and lift the marks from the dates that qualify.
(even Job would be tested)
I'll dig out a siutable example from my library and post back.