What used to be a unique plate block of eight stamps eventually ended up as a plate block of four stamps. Actually, this was at best a plate block of six stamps. For flat plate printed stamps, the preferred plate block size is a number centered block of six stamps.
There is evidence that perforation separation had already occurred in the block of eight stamps regarding the leftmost two stamps, especially the leftmost top stamp. However, it was separated rather than left as an intact block of six stamps. Y. Souren and Amos Eno removed the left four stamps from the plate block, giving it its current format as a block of four. Today the four leftmost stamps are all each single stamps.
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