Q. Is it correct when someone speaks at a wedding on Tu Beav to already wish everyone a Kesiva Vechasima Tova or is it out of place?

A. Chasidic sources maintain that it is proper for one to salute from Tu Beav onwards with the blessing of Kesiva Vechasima Tova (Darkei Chaim Vesholom 683 on Munkatcher traditions, Nitey Gavriel Ben Hametzarim 2: 98: 15) One reason given is that from that day onwards one has to increase his learning of Torah as the days grow shorter (Ta’anis 31a) therefore, the sparks of holiness of Rosh Hashana and the days of Rachamim begin to awaken and glow (ibid.)

Rabbi A. Bartfeld as advised by Horav Shlomo Miller Shlit”a