Solution
Yes, if you have a Release in Spira and it has Test Cases already associated with it:
![](/Support/Attachment/150447.aspx)
Then you can use the special shortcut to Create a Test Set from the Release:
![](/Support/Attachment/150448.aspx)
When you do that, a new test set will be created, with all of the test cases from the release in question:
![](/Support/Attachment/150449.aspx)