Why Li Chun appears in BaZi products
BaZi is not only a lunar-calendar system. It also works with solar terms, seasonal qi, and time boundaries that matter because they change the chart climate.
Li Chun is the first solar term of spring, and many charting approaches use it as the annual handoff for astrological year logic. That is why a user born near early February can easily be assigned the wrong zodiac year by a shallow tool.