20 October 2016 - 12 x 2nd class blue booklet with source code MTIL - 2018 printing on SBP1
Cylinder numbers: W6 (blue), W1 (iridescent) W3 (phosphor) - the numbers are hidden by the front cover of the booklet.
A new printing was made on in 2018 (packing date not known) on SBP2 with year code M18L (listed here as ME 7a.8) Printed by Walsall Security Printers.
SG GB Concise catalogue - new number expected to be ME7a
A further printing on the remains of SBP1 paper was made during the summer of 2018 and has been seen in packs dated 05/12/18.
No cylinder booklets available at this stage