What does it mean to renovate old calendars?

Times have changed and ideas have changed. The change of customs and people's feelings is related to the rise and fall of the country.

Since calendars are all given by the emperor, it is obvious that old calendars should be carefully preserved. Therefore, everyone gave an old word to the old calendar, calling it the old imperial calendar.

The old almanac is not very practical for the New Year, so it has gradually become a derogatory term, generally used to describe some conservative thoughts and behaviors.