The Men of the Great Assembly make this decision and give us what is known as the Hebrew Bible today — or the Tanach. (Tanach is a Hebrew acronym which stands for Torah, Prophets, Writings.)..
And yet, friend, the Sadducees and the Samaritans both rejected the Prophets and the Writings, while the Ethiopian Jews accepted both these and the 7 deuterocanonical books.
Secondly, you state the date ending in 310 BC -- was the canon "closed" at that date? No, they were not "closed" -- the canonization process did not end until c 200 AD
The Torah was canonized c 400 BC, the Prophets c 200 BC but the Writings only by c 100 AD and that too, it was closed by Rabbinical Judaism (Phariseeism) yet even then, post Jamnia there were disputes over the Book of Esther and Ecclesiastes and the Song of Songs
Even so, the Midrash Koheleth describes 24 books, but Josephus describes only 22 rejecting Esther and Ecclesiastes which were not yet considered canon.
I do realize there are alternative histories and timelines. That’s just the point. The ‘Jamnia Council’ story of the canon is a hypothesis not accepted by the consensus of Torah authorities.