How SPX behavior can change near a Gamma Flip band
An illustrative methodology study showing the difference between a static level and a moving sensitivity zone.
Session setup
Assume SPX opens just above the estimated flip band, net GEX is near zero and 0DTE gamma is concentrated in two adjacent strikes. The information is not a single flip number; it is system fragility. A small move in price or IV can redistribute hedge sensitivity quickly.
What to monitor
Track SDPI persistence, spread width, volume migration and the ES response. If price rises while SDPI stays weak and the fair-basis residual does not confirm, the better interpretation is incomplete pressure — not a proven direction.
The transition
In the scenario, price crosses the band while Dollar-Delta, liquidity and sustained SDPI align. That confluence makes positive-pressure continuation more plausible. A price move without persistence or with degraded source health does not raise the Evidence Score.
Conclusion
A Gamma Flip is not guaranteed support or resistance. It marks a zone where system sensitivity can change. Its value comes from combining it with flow, liquidity and futures, then defining invalidation.
Every hypothesis must carry its evidence, alternative explanations and invalidation.