Is the date of the constellation based on astrological date or astronomical date?

The date of the constellation is calculated according to astrology.

For this question, you have to make clear the difference between the Chinese zodiac and the Chinese zodiac. Constellation refers to the map that regards the stars as plane figures, while ecliptic refers to the twelve constellations (in fact, there are thirteen more) on the earth's orbital plane. The ancients observed the sky and found these twelve constellations, and called their areas, such as Gemini's, Gemini uterus. So the palace refers to the sky and the constellation refers to the earth. Originally, there should be a one-to-one correspondence between the two, but because there is something called precession in the movement of the earth, the zodiac is misplaced. Astronomers set dates according to constellations, while astrologers use houses to set dates, so it's different. Usually, "which constellation are you from" means astrology, but astronomy generally doesn't say the date of the constellation, because the date of each constellation is different in each region, so the date of the constellation is calculated according to astrology ~