If the shutdown ends after hours, applies to the next trading day as an increase from prior close -> end of day. Examples:

• If the shutdown ends at 2pm on Nov 12, market is based on the change between the closing price of SPX for that day, and the closing price of the SPX Nov 11

• If the shutdown ends at 8pm on Nov 12, market is based on the change between the closing price of SPX on Nov 13, and the closing price of the SPX Nov 12

• If the shutdown ends after hours Friday or on a weekend, resolves to the change between Monday close and Friday close.

• Likewise for trading holidays, uses next trading day vs previous trading day