Wednesday, 8/15/2018 (Expiration Wednesday)
Trade 1 (9:57:12 am, PT) ← SPX trading around 2815
sell -4 August 15, 2018 2795 puts at $0.80 (delta 10)
buy +4 August 15, 2018 2750 puts at $0.05 (cheap wings)
max profit: $0.75 x 4 x 100 = $300
Trade 2 (12:30:15 pm, PT)
buy back short puts (2795) at $0.05 (to remove the risk)
let long puts (2750) expire worthless
PROFIT: $280 (in 2.5 hours)
Note: SPX closed at 2818.37 at 1:00 pm, PT