In June 1922 the first issue of low value coil stamps were released, see figures 1-5.
Coils were made up by Harrison and Son Ltd., London from vertical strips of 10 stamps or horizontal strips of 12 stamps, taken from sheets of 240 stamps, which were printed by Harrison & Sons.
Strips were joined using part sheet margins to make-up either vertical rolls of 500, ot 1000, or horizontal rolls of 480 stamps respectively for dispensing machines. Production of coils with 1000 stamps was very limited. The source sheets had both die types of the 2d. stamp.
In the case of the Irish coils, the overprinting of the GB sheets, was also contracted to Harrison’s. With particular reference to the 2d. stamp, overprints were first applied to GB sheets printed from a die 1 engraved working plate. In August 1922, Harrison’s printed 2d stamps using a die 2 engraved plate. As a result, vertical and horizontal coil stamps are recorded with either die types 1 or 2, and although very scarce, with a mix of both die types, from vertical coils.
For the 2d. stamp’s die distinguishing features, see OVERPRINTS Pt.3. Distinguishing Stamp Printings between Die 1 & Die 2 Plates.
Hibernian Handbook and Catalogue of the Postage Stamps of Ireland, 2020 edition, Part 1.
Information provided by Barry Cousins.