Answer from Automic:
Automatic
setting the release of a package can be done using ARA ImportExportCLI. You'd
need to do the following steps:
1)
Export the created package via "export" to xml or csv: Exported file
will contain the property system_release.system_name which is empty.
2)
Adapt the exported file to set the name of the release and then import it with
"import" command: Release of the package will be set. Note: To get
the list of Releases you can also use the ARA "export" function.
You
can use ImportExportCLI either by command-line tools or by directly calling the
WebService. Please see "ARA Integration Guide", chapter 3 - Import
and Export services.