In the eight characters, May starts from May Festival and ends in June Festival, which is a little hot.
That is to say, it is a slight summer heat on May 20th 12:00 of the lunar calendar. After that minute, 12:0 1 is June (not). A year is divided by beginning of spring time, and lunar days are divided by 23:00, understand? If you don't understand, you can keep asking questions.
If it helps you, please adopt it!