Diamond Blue 1st class Machin - Security Codes

We're reliably informed that security codes are present on the Diamond Jubilee Machin definitives from booklets - and probably business sheets and possibly the miniature sheet.


The booklet code is the letter T as usual (for Twelve).  The changed text is behind the hair 'bun' on the Queen's head where MOND reads MTND.  We do not expect any year codes as this colour will only be issued in 2012.  

The code for the Miniature sheet is MMND in the same place, and I think we can safely assume that the code for business sheets is  MBND.

Pictures as soon as we have them.

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