The spring equinox marks the passover season, the autumn equinox marks the actual birth.
Wonder what the ‘summer solstice’ marks?
No, Luke has Jesus conception at the 6 month of Elisabeth’s pregnancy.(She hides her self 5 months “and in the 6th month Mary gets her “good news” and then goes and visits her cousin Elisabeth... all in Luke 1) There is nothing that points our to the exact time of year. Gestation periods are 36 to 40 weeks and they didn’t have exact tools like we do today to closely “guestimate” dates of conception...John would have to be born before Jesus and be preaching for some time before Jesus arrival as he was the prophesied Elijah(in spirit) who would be the herald of the coming Messiah. It might be the date you claim...if Jesus was born in mid September as it would be about 40 weeks from that time.(with John being born about late March Early April say near the day of Passover or near the day of “first fruits”?!)