They key to an intraday/swing short is 2546.25. --Need to breach that and have it become new ceiling.
Now we've breached the second support level of 2543.75. Next support is 2539.25. --Should be attempts to put in floor at 2543.75 and/or 2539.25
What I would look for is a bounce off one of these levels and then the intraday/swing short could be taken on fresh downside momentum.