"Controlling the progress is the process of monitoring the status of the project, updating the project progress and managing changes to the progress baseline. The main function of this process is to maintain the progress baseline during the entire project, and it needs to be carried out throughout the project."
"To update the schedule model, you need to understand the actual performance to date. Any changes to the schedule baseline must be approved by the implementation of the overall change control process (see section 4.6)."