Duplicating an item is just like copying and pasting but with an exception. In the case of Symphony when you duplicate an item using the user interface you are unable to modify the publisher or site when you edit it - everything else you can adjust. The other little insight is when you have the placement naming convention set to auto generate and after making a change to your duplicated item this will automatically be adjusted for you upon save.
Let's have a look at how this works. From your media schedule select an existing item and then from the sub menu click on the document icon. A drop-down menu will appear for you to then select the duplicate function.
Once the item has been duplicated you will receive a successful message and you will also be able to see the new placement in a blue colour.
To make a change all you need to do is select the item and then click on the pen icon in the sub menu for the pop-up box to appear. As highlighted you will be able to modify everything except for the publisher and site values.