Risk of an option being exercised after the market closes extends until approximately 5:30 PM New York time the same day.
The strategy I like to use when Vols are high is to own the product and sell the at the money straddle and hold it through expiration. Upon expiry, The Stock gets called away and you keep all the short premium for a nice profit Or an equal amount of product is deposited in your account and you have scaled in or have a lower cost basis. Then I sell another at the money straddle and do it again.
The strategy avoids going back to the option market to unwind your position. Those market makers only see you once.