Just for the record: According to "Filmové informace" (43/1965, 1965-10-27, page 4) the short was theatricaly released with feature length movie Lásky jedné plavovlásky. According to Filmový přehled the release of this movie was on 1965-11-12, which I further confirmed in "Literární noviny" (46/1965, page 10).

We really need some tool to make notes...