Configuration manager added a new option for collection called the maintinence window. Its define a specific period of time within which changes can be made to clietns that are members of that collection.
For example, if you have set of computers that should only receive software updates and other advertisement between 1.30 A.M to 2.30 A.M midnight.In such cases you can use maintinence window for that specific collection.
A maintinence window cannot be longer than any given 24 hours period. If you need a longer maintinence windows, create multiple windows for collection.
How to configure a maintinence windows for a collection
Configuration Console —>Computer Management—> Collection—> Right click—> Modify Collection settings—> Select maintinence window—> New—> set start time and end time.