I am in the process of disposing of my collection and came upon a copy of 859 (in position 42 as part of a lower left plate block) with a circular spot as per the attached image. My Unitrade catalogue is 2012 so perhaps it is in later editions. It almost matches the size of the perforation holes but doubt if this is an issue. Surely perforation takes place after printing.
Can anyone throw any light on this?
