Option Millionaires

[Newly2b]

While SPY closes trade at 4 pm NYC time, SPY's options don't close until 4:15pm NYC time. I always assumed that the 4pm close on the underlying was used to determine whether or not an option was ITM, OTM or ATM.

My question is, if SPY's price closed at 4pm above 206, but then fell below 206 in AH trading but before the option closed trading at 4:15pm, would a 206 Put be considered to have closed ITM and the buyer able to put the stock to the option seller?

Would appreciate anyone's thoughts here. TIA

Newly