There are thirteen months in the Hebrew calendar this year. It's how the leap year is done.
My thought is with Aries, the Ram/lamb constellation. The sun is still in Pisces and won’t be in Aries until later this month..
Jewish folks like Josephus and philo have noted that passover was always when the sun was in Aries., the Ram
And that would mean the seventh month would be in Libra, the scales.
The wobble of the earth has changed the constellation sign’s timing now with Pisces holding the equinox..
Could very well be God’s design or maybe the growing seasons have changed a little so that their is more harvesting done in late October/november...
Seems odd that feast of tabernacles could be over and the Jewish famers are out in the fields a month or two after it, bringing in their ‘ingathering’ after celebrating it...