This feature is available in Ultimate edition only.
The Regression Planning page gives you summary views of regression tests and suites, as well as the ability to drill down into detail views where you can make updates to them or associated assets (regression tests, test sets, links, and attachments).
Deleting a regression plan requires that it be empty. Deleting a regression suite requires that no test sets be associated with it. So, to delete you must first delete any test sets, then delete regression suites, then delete regression plans, strictly in that sequence.
Go to Release Planning > Regression Planning.
From the Plan Type list on the left, click on the plan or suite you want to view/update.
The Summary window opens for the selected plan/suite. This view includes rollup data for the tests currently under each regression plan and suite. Suites also show all associated regression tests and test sets generated from the suite.
Click Edit to open the Regression Plan/Suite page, or click on the plan/suite ID to open the Details page and click Show Relationships to view/edit any associated regression tests, test sets, links, or attachments. To delete a plan or suite, click Delete on the far right (see note above about deletion rules).
If making updates, click Save.