What I expected to happen was the trajectory would reset when i would go through the portal after running out of the levitation effect. What really happened was that when i would go through i would reach the other side and die.
Steps to recreate.
1. Use the levitation effect by doing /effect @p minecraft:levitation 100 10
2. Center your fall on the end portal.
3. Wait until it runs out or use /effects @p clear from a hight you would die from
4.Fall into the portal.