Managers are able to view all system level data but cannot modify it. Additionally, by default, Managers are not able to approve roster changes that affect other Managers. I.e. a Manager cannot approve leave for another Manager, they cannot publish a "Change Rostered Shift" for another Manager, etc.
Managers can make DRAFT versions of the roster changes for other Managers but are not able to publish them.
This restriction can be overridden on a Manager by Manager basis in the Configuration -> System -> User page.
In the user list, select the Manager to whom you wish to give this higher level of authority. Then in the Edit User -> Permissions panel, when Manager is ticked, an "Allow Manager Approval" check-box is available. If this check-box is ticked a further check-box, "Restrict To Team", becomes visible.
If neither of these two checkboxes are ticked then the Manager will be prohibited from publishing changes that affect other Managers.
When only the "Allow Manager Approval" check-box is ticked then this Manager will be able to publish changes that affect any other Manager.
When the "Restrict To team" check-box is also ticked, this Manager will be able to publish roster changes to Managers that are in the same Team for which this Manager has been set as a Team Manager. They will still be restricted to only creating DRAFT changes for Managers in other Teams.
If a user is also set as an Administrator, they are able to publish changes to any personnel, regardless of the permissions set at the Manager level.