How to freeze operations within a frozen period
1.In the project settings, check the property “Enable scheduling freeze period” in the Time periods tab.
2.In the project settings, specify a value for the property “Freeze period end time”.
3.For the resource you want to auto-freeze, change the value of the property “Freeze period end time” to D.
4.Select [Schedule] – [Auto-Freeze Operations…] from the main menu.