Thanks to the web site of Norvic Philatelics( Ian Billings) I can now post (actual) images of the two new 20 gram airmail stamps for Europe (dull green) and Worldwide (light mauve)
I have tried comparing the colours to the equivalent sheet Machins, 60p (Emerald green) and 97p (mauve) it seems to me they are of a completely different shade.
All the new Machin definitive and country stamps will be printed by De La Rue in gravure, in sheets of 200. Cylinders D1 D1.
The 20gr airmail booklets are printed by Walsall Security Printers Ltd, cylinders known to date for the booklets of 4 + 4 x airmail labels are W1 W1 W1