What does a Maintenance schedule specify?

A maintenance schedule primarily outlines the periods during which regular maintenance activities will take place, which helps ensure that systems and services remain reliable and stable. This schedule often incorporates times for planned maintenance, updates, and other necessary actions that can impact the availability and performance of services.

The correct choice highlights that change requests should be scheduled during these specific times. By doing so, organizations can minimize the disruption to business operations and enhance the planning of changes by ensuring that all relevant changes are executed during predefined windows. This allows teams to conduct maintenance tasks without interfering with daily operations.

Other options describe activities related to maintenance but don’t directly relate to the specific specification of what a maintenance schedule entails. For instance, specifying times when change activity is restricted might be a part of operational procedures but isn't limited to a maintenance schedule itself. Scheduled system upgrades and training periods may happen separately and are not universally included in a maintenance schedule.