Awakening from Below - Until 499.5

• Avraham Avinu was born on Pesach in the year 1948.
• Yetziat Mitzraim was in the year 2448.

While the Geulah was in Nissan, it was in Tishrei, a half year prior, that the plagues started, and the slavery ended.

That is to say, from Avraham Avinu's birth, there were 499.5 years of Awakening from Below, and then the final 1/2 year which was the Awakening from Above.