What is a club? Why can't the new grave sweep the grave?

Clubs are divided into spring clubs and autumn clubs. The Spring Festival refers to the fifth May Day after beginning of spring, and the Autumn Festival is also the fifth May Day after beginning of autumn. For example, this year (20 10), beginning of spring was on December 21st of last year, the first day of the Reform Movement, the 24th day of the Reform Movement, followed by the second day of the Reform Movement on the 4th day of the first month, and then the fifth day of the Reform Movement. Some years of the Spring Festival are before the vernal equinox, while others are after the vernal equinox. There is a saying in many places in our country that "new graves are not enough for social use". It refers to sweeping graves in front of the Spring Festival Club (people who died in the previous year or that year, and some areas died within three years). For example, "History of Fu Nan" says: "The new grave is sacrificed in front of the country, and both men and women in the family go." According to my very limited experience, this custom exists in most places such as Hunan, Hubei, Jiangxi and Guangdong. So why is it that "the new grave doesn't pass the club", that is, why should we sweep the new grave before the Spring Festival club instead of going to Tomb-Sweeping Day to sacrifice with the old grave? Generally speaking, ancestor worship is held in Tomb-Sweeping Day in March and Ghost Festival in July and a half, especially in Tomb-Sweeping Day, which is the custom in most parts of China. It is to commemorate our ancestors and offer sacrifices to them. For those who don't die long, they think they have just arrived in the underworld, unaccompanied and lonely. Sacrifices brought by relatives in Shi Yang will always be taken away by other wild ghosts. It is said that in front of the club is the legal reception day of the underworld. During this legal time, the new deceased can receive all the sacrifices brought to the new deceased. Of course, whether these statements are true or not, I have never been to the underworld to experience life, so I can only follow them.