>When editing you can select all the features you want placed or unplaced.
>Right click and open the attribures.
>On the left hand side of the Attributes window, select the top line (Name of the feature class you are editing) to select all of the selected features.
>On the right hand side of the Attributes window, select the Attributes tab.
>In the value field click the Status row.
>A dropdown will allow you to changed the selected anno to placed or unplaced.