5.42 PM ET: After reviewing all the combinations, these are my thoughts.
1. I'm convinced 20A is true WITHOUT 1820 REQUIREMENT, closer to 1760.
2. So that means 19A is true until it is not.
3. That just means that while I expect the floor to be 1820, it can be 1780, and that would be fine.
4. So strategy does not change. Short 5.10 to 5.11, close 5.12 to 5.13.
5. Entry for 20A is same as 19A exit.
6. How do you know when it's done? You don't.
7. Odds favor low being 5.13 FRIDAY 3 AM.
8. 300 pts swing from bottom.
9. Whether 1780 or 1840, it's 300 swing