What does it mean that September 2nd is the Mid-Autumn Festival?

Mid-Autumn Festival is a traditional festival in China, also known as July 30th, July 14th, Ancestor's Day, Orchid Festival and Local Officials' Day. Festival customs mainly include ancestor worship, river lanterns, sacrifice to the dead, paper ingot burning and land sacrifice. "Mid-Autumn Festival" is the name of Taoism, which is called "July 30th" (or "July 14th") in folk customs. Its appearance can be traced back to ancestor worship and related festivals in ancient times. Festivals are related to the cycle of yin and yang in ancient culture. In the Book of Changes, "seven" is a constantly changing number and a resurrected number. July is auspicious month and filial month, and July 30 is a festival for people to celebrate the harvest and reward the earth in early autumn. Some crops are ripe, so people need to worship their ancestors and report Qiu Cheng rice and other sacrifices to their ancestors. This festival is a traditional cultural festival to commemorate ancestors, and its cultural core is to respect ancestors and do filial piety.

September 2 this year is the seventh month of the lunar calendar 15.