How many years elapsed before Israel's sojourn in Egypt began?
According to the timeline, 215 years elapsed before Israel's sojourn in Egypt began. This period falls within the 430 years from God's promise to Abraham until Israel's national exodus from Egypt, placing the start of the Egyptian sojourn at the midpoint of that span.
Les teaches that God promised Abraham that from His call to go to the land of Canaan until Israel would be a nation coming out of Egypt would be 430 years. He notes that the exact middle of that 430-year period is when Israel begins her sojourn in Egypt. Thus 215 years elapsed before the sojourn in Egypt even begins. Les also corrects the impression that the Israelites were in slavery and bondage for the whole 400 years.