There’s a double bottom in the S&P 500 (SPX) 4470.00 area. This corresponds with daily volume profile support on the S&P 500 – December 2021 E- Mini futures contract.
The 15- minute SPX chart courtesy of Trading View illustrates the support zone.

If the SPX breaks below 4468.99 there’s no significant chart support until the 4370.00 area. A break below this important support could open the door for a rapid move down to 4370.00
Traders are 100% short non-leveraged SPX related funds as of the open of the SPX session on 09/09/21.
Traders add an additional 50% short non-leveraged SPX related funds on an SPX move below 4468.99. Use a move above SPX 4529.90 as a stop loss for the 50% position. Maintain prior recommended stop loss levels for the 100% short position.