All of you that trade SPX have probably noticed this but since the advent of the daily expirations the market makers try to hold onto that time value until the last day/minutes. They also manipulate IV of the individual options. We watch it on the algo.

1 of my SPX butterflies is solidly under the tent and has huge profit potential. I have been in the trade 20 days but until today it was showing negative. 6k of that theta decay finally transferred today but there is still another 11k sitting there.

The way to force the time value in SPX is to hold into the close and force them to pay you the time value. Unfortunately since Schwab took over TOS they will not let me hold until the close. I get messages throughout the day saying if you do not close it their risk department will. Often at a market order.

Tastytrade allows me to do that as long as they can tell I am watching it. In an ideal world I have taken my profits long before this but occasionally have to carry one of these into expiration. But if you do watch the gamma, it can flip your profits to losses quickly.

Not an issue with stock or ETF options as you can just force exercise to keep all the time value. Only an issue in the indexes because you cannot really own the index other than through futures but with futures you can force exercise of the futures.