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GB.FIRST DAY COVERS - 1965 3d deep lilac phosphor on illustrated cover with Southampton cds, together with x2 3d phosphor deep lilacs and 4d deep ultramarine with Southampton machine cancel. The 3d is listed as 615ca but dated as Apr 65 in Concise. However, on May 17th, 3d rolls werre switched to single band stamps. THis new date has not been noted in the Concise (2).