I recently got a stamp with an interesting error...
1945 Maribor provisional issue, No. 8 with missing "1" in "12". Signed Ercegovič.
Missing "1" and some red paint inside "2" suggest that there was some dirt on the cliché during the printing. This mistake is unknown to me. I think it is an occasional error fixed by cleaning up the cliché as soon as it was noticed.
