At which meeting did China decide to officially designate the Gregorian calendar 1 as "New Year's Day" and change the first day of the first lunar month to "Spring Festival"?

19 12 When Sun Yat-sen became the provisional president of the Republic of China in Nanjing, he announced the abolition of the old calendar and used the Gregorian calendar to mark the year of the Republic of China. And decided to take 1 91265438+10/month1as the first year of the Republic of China. January 1st is called New Year's Day, but not New Year's Day. However, people still use the old calendar, that is, the summer calendar, and still celebrate the traditional New Year on February 18 of that year (the first day of the first month of the year of Renzi), and other traditional festivals remain unchanged. In view of this, 19 13 In July (the second year of the Republic of China), the then Beijing government, as the chief of the interior, submitted a report on the four-season holiday to President Yuan Shikai, saying: "It is an old custom in China to have a holiday every year, that is, it should be expressly stipulated that New Year's Day of the lunar calendar should be designated as the Spring Festival, Dragon Boat Festival as the summer festival and Mid-Autumn Festival as the autumn festival. However, Yuan Shikai only approved the first day of the first month as the Spring Festival, and agreed to have a routine holiday during the Spring Festival, which will be implemented the following year (19 14). Since then, the beginning of the summer calendar has been called "Spring Festival". 1949 On September 27th, the first plenary session of China People's Political Consultative Conference decided to adopt the world calendar year while establishing the People's Republic of China (PRC). In order to distinguish between the solar calendar and the lunar calendar, the first day of the solar calendar is called "New Year's Day" and the first day of the first lunar month is officially renamed as "Spring Festival" because the "beginning of spring" in the 24 solar terms is just around the lunar year.