This feature is available in all editions.
Items in the backlog are "unscheduled" and must be assigned to a release/project to "schedule" them.
Option 1. Drag and Drop
The items in the backlog grid on the left are "unscheduled". In other words, they have not been added to a project/release. Follow the steps below to use drag and drop items into a project/release. Note that once "scheduled", the work item is removed and no longer displays in the backlog grid on the right.
From the main menu, select Release Planning > Release Scheduling.
If not already selected, select a project from the project navigator.
Select an item in the backlog grid on the right, and then drag it into a project/release on the left.
If a portfolio item contains any child work items that are assigned to other projects/releases, the system lists them and asks if you want move (or unite) them to the same project as the parent portfolio item:
Click Yes, unite these work items to assign the work items to the same project.
Click No, leave them there to leave them in their current project(s).
Option 2. Schedule Inline in the Grid
You can also schedule a work item into a project/release directly from the grid. In order to do so, you need to first make sure the Project column is visible on the grid. If not, follow the steps in Adding a Column to a Grid. Once added, follow the steps below.
Double-click on a row to make it editable, and then select a project/release in the Project column.
Repeat Step 1 to assign more work items.
Click Save, and then refresh the page.
Unscheduling/Removing a Work Item from a Release
To unschedule (or remove) a work item from a release, simply drag it from the release, and then drop it back into the grid.