I thought it started last september...
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It has to start at the beginning of a Sabbath of years.
That means it has to start at the beginning of the month of the Aviv barley, of the first year of a Sabbath of years.
Aviv, one year from today would be the first possibility, and Aviv 2021 would be the next after that, and so on.
It cannot happen in the fall; the Aviv barley comes shortly, after the vernal equinox usually, And the Biblical year cannot begin in the fall. (The Pharisees declare Rosh Hashanah in the fall, but they know that it is really in the spring)
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