Thanks Cjd. It's a nice variation.
Here's another of my John Ash blocks. Also a favourite of mine, and not too difficult to acquire.
Centenary of Western Australia, 1929. Issued 28 September, 1929.
Unwatermarked. Perforation 11, single line.
And there's a couple of variations to this stamp. one of which is outlined on the re-entry thread:http://goscf.com/t/76290