From Viet Hustler's analysis yesterday:
However, noteworthy is that from yesterday and through today, the amount of negative delta across the market still keeps SPY's call wall at 440 while SPX's call wall moves up to 4450. Currently, 440 is a key important level for SPY in this week's October OpEx with high likelihood SPY will pull back here and not break above 440 at least until end of OpEx. The sentiment and actions of investors and traders in the market from yesterday and today largely reinforce the above assessment.
SPY's resistance at 440 also coincides with VIX options expiration tomorrow with a large amount of 15P and 20C expiring. After tomorrow's VIX OpEx, market volatility will gradually increase strongly heading towards Friday's OpEx, creating additional downside risk with the 430 put wall level important level of SPY.
