This thread has prompted me to dig out the three-fold chart shown on the attached pics, dated on the cover to 24 Mar 1942.
It shows the rank badge backings and arm of service strips existing at that date and has attached with a treasury tag four strips introduced after the original series in September 1940. These include the exceptionally rare - and oft disputed - strip for the Army Air Corps which was never worn.
This particular chart will be offered for sale by Robin McGregor in his Christmas sale on
https://www.mcgregor.uk.net/ which runs from 19th to 26th December.
To add to the mix I have also attached an example of a printed arm of service strip.
Jon