In Leviticus 23, God's festivals are called appointed times. One appointed time for ancient Israel was the fulfillment of the 70 Weeks prophecy of Daniel.
Because Abraham trusted God, his descendants have received unprecedented blessings. If the Israelites would have kept God's law, they would have served as a model.
The Day of Atonement is not fulfilled with the binding of Satan. Rather, there are numerous prophecies of God atoning for the sins of physical Israel.