You can choose how your workflow statuses update automatically by using Automators. To make changes, go to settings from the main menu, and select Workflow then select the tab Automators.
Each of these Automators lets you adjust the following:
Choose what status a planned work item will be given when it reaches its start date
Choose what default status an email will be given when it is assigned to someone
Choose what default status a note will be given when it is assigned to someone.
Choose whether the start date for a work item will update when its status is manually changed from Planned to In Progress
Choose what status a new task will be given
Choose whether a work item will have its status update to In Progress when the first task within that work item is marked Completed
Choose to update the status of work when 5 client task reminders have been sent to the client and are still incomplete
Choose whether a work item will have its status marked Completed when all tasks within that work item are marked Completed
Keep in mind, any changes you make to your status settings will immediately go into effect across your whole team.
Best Practice Tip:
Often times when a work item hits its start date, it's not always "In Progress". Consider using the status, "Ready to Start" and apply this to "When Planned work reaches its start date, update its status to "Ready to Start".
This will help identify work items that are truly "In Progress" vs. an alternate status like "Ready to Start".
Note: you will need to be an Admin user to adjust these Automators and other Settings.