SPX IVR > 50

45 DTE Put
5 Delta
50% MP
Exit 21 DTE
2x Stop (option price hits 3x credit)

SPX IVR < 50

2-3 DTE Put
5 Delta
2x Stop (option price hits 3x credit)

Entry time is EOD (depending on your broker, SPX options can be traded up to 4:15 PM ET)