1p maroon Machin definitive from counter sheets
The stamp was printed by ISP Walsall with year code M18L 09/05/18 with blue phosphor, and distributed by Royal Mail Tallents House on 12/09/18 at the same time as the earlier printing. On this printing the transparent iridescent ink with the words ROYAL MAIL has yellow fluorescence.
The second printing of this stamp was on 22/08/18 and was available from Royal Mail in December. This printing has blue phosphor, but with no yellow fluorescence.
SG U2920 - same number used for previous years
Cylinder blocks of 6
Date blocks of 8 - 22/08/18