The red-and-green postage dues of Australia were printed using one of two (or sometimes both) frame plates.
I have been researching the 1931 2d on CofA paper perf 14 (SG D102) and saw the following flaw on four separate stamps (one illustrated here):

At 1.30 from the 'E' of 'DUE' you can see a white void in the right margin. I have this on 4 examples but it is not mentioned in 'Commonwealth of Australia: The Postage Due Stamps 1902-1961', R P Hyeronimus, 1980.
All the examples were single stamps.
A later issue of these stamps (SGD107) was pef 11 x 11 but printed on frame plate 2 as well.
A block of 36 of these helped me position the flaw within the sheet.

The subject stamp is three from the bottom on the right-hand side of the sheet, more detail in the image below.

The position of the stamp is constant. Some discovery fun along the way. It is from frame plate 2, right pane, position 48, abbreviated as FP2 RP48.
I hope to have the pages for this value completed shortly and will post them up when done.