Pashtus according to many Rishonim (though not all) is that there is no Inyan to learn 30 days before any holiday except for Pesach and Sukkos. Also, if I recall correctly there are a few Rishonim (maybe only one?) who say that there is no Mitzvah to learn 30 days before a Yom Tov D’Rabannan (assuming that such a thing exists).
I certainly don’t recall any rishonim who say to learn the halachos of Yom Haatzmaut.