Your BaZi Month Doesn't Wait for Midnight.
Two people can share a birth date and still fall on opposite sides of a BaZi Month Pillar boundary. That sounds strange if you expect every month to begin at midnight on the first. In the Jie-based Four Pillars convention, however, the month changes at a solar-term instant. Your recorded date does not need correcting just because the chart's month label surprises you. Only twelve of the twenty-four terms start these months The Hong Kong Observatory explains that the twenty-four solar terms alternate between twelve minor and twelve major terms. In this BaZi convention, the twelve Jie, corresponding to the minor-term set, mark Month Pillar transitions. The intervening major terms, often called Zhongqi, do not each begin another BaZi month. The Lunar calendar library's Four Pillars documentation likewise specifies the instant when the relevant Jie begins for dividing a month pillar. This is a calculation rule within a tradition, not evidence that a chart predicts anyone's...