Update and edit derived parts and assemblies. You can also update a part manually or defer updates.
When a base part or assembly is modified, the derived component appears with a lightning bolt in the browser, indicating that it is out of date. To incorporate changes, you must update the derived part; it is not updated automatically.

On the Assembly tab of the Application Options dialog, selection Defer update.
When this option is selected, you’ll need to manually update to incorporate changes that affect derived parts.
Right-click the derive feature in the browser and choose Edit Derived Part or Edit Derived Assembly.
Use this option to change the objects you chose when you originally derived the part or assembly. Updates are automatically reflected in the current file.