Zagreb provisional issue has been in use for only six days, from 25th to 30th of Jun 1945. It is known that usage was tolerated for additional ten days, but only for official use.
1945 Zagreb provisional issue, stationery sent from Valpovo (12.VII.45) to Ljubljana. The stationery was not accepted for postage, so 1 Din was accounted for in cache and marked accordingly by rubber stamp. Very rare example of non official use after the expiry of postal validity.
