Separated Heisei 1 and 2 to Heisei 1 1, Heisei 1 2, Heisei 2 1, Heisei 2 2. This should fix the loading and most crashing problems. Heisei 2 2 might take some time to load. Reiwa and Showa are still the same. If this doesn't work out, I don't know what will.