From the CME Globex Control Center, here is the summary of KEY changes, per CME market segment
Monday, May 30, 2022 – Market “HALT” > then reopens Monday night at normal times.
**Any open positions must meet Exchange Maintenance Margin 15 minutes before the market halt (11:45 am CST).

View Full List: https://www.ampfutures.com/trading-info/holiday-hours/