In order to try to explain these types in plain language I have now managed to find some images on the web which show the position of the wording compared to the diadem, this may help.
Type I: This is found on stamps on which the word 'MAIL' is unchanged and also with the word 'MAIL' having a substitution of the letter 'A'. This code is situated across the top of the diadem.
Type II: is shown, with the word FOYAL forming from (coming out of) the central cross of the diadem.
In reality the secondary codes MAIO, indicating the year of issue should also be placed in a different grid positions on these stamps, but will (should) correspond to the same three code types shown.Thanks go to Delta Stamps for the information and images.
Deegam reportsAnother news snippet that has come my way via Charlie and the Machin Forum.
"You may also like to know that The latest Deegam report has been put on the website for those who are subscribers."