The time of the promises draws to a close when one of Jacob's sons, Joseph, is sold by his brothers into slavery in Egypt.
When they did this, they did not realise that they themselves would later settle in that land.
Furthermore, and their own great grandchildren would become slaves there after Joseph's death.
Joseph's bondage in Egypt was a kind of figure of the bondage that his family was going to suffer some three generations
The time of the promises ends where the book of Genesis ends.
The children of Israel settle in Goshen, with Joseph as their ruler
"So Joseph dwelt in Egypt, he and his father's household. And Joseph lived one hundred and ten years". He saw his great grandchildren before he died.
"I am dying," he told the family, "but God will surely visit you and bring you out of this land to the land of which he swore to Abraham, Isaac, and Jacob"
The time of the promises to Abraham spans the generations of Abraham, Isaac, and Jacob. It also includes the marvelous story and time of Jacob's son Joseph.