Something looks just odd with the quotes I am getting. Looks like the premiums have changed asymmetrically during the weekend. The 3225 calls only went up 3.5 but the 3225 puts dropped 14.5 Today's expiry. So selling a straddle before the close was 37 and now it could be bought back for under 27. Does this happen over most weekend or am I looking at the wrong numbers? Well, I will keep an eye on them in the next few days and see how often this happens. Edit: I see the same with SPY and SPX options. The put side for SPY collapsed 1.50 while the call side only gained .30
If implied vols decline, then on rallies the calls wont gain much while the puts decline at an accelerated pace.