Interesting! My PN has last (recorded!) amendment as AL 6 dated Dec '69. The pages I have quoted were all part of AL 6, which may - or may not - be significant.
The date would tie in (ish) with the move of 78 from Aden to Sharjah; presumably Aden would have been the only theatre for the 20lb HE for the Mk2.
Calling any Aden vets!!!