This feature is available in Enterprise and Ultimate editions.
You can use the Release Scheduling page to gain insight into a release/project to better optimize release plans during your release capacity planning activities. You can see release capacity details that show bottlenecks early and so you only commit to work that can be successfully completed.
Release capacity details don't automatically show up. To see capacity values, you must first enable/configure them by entering Target Swag and/or Target Estimate (depending on what you use for release planning) for each release/project. Once enabled, you can see capacity details in the release progress bars and and in the summary sections.