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Do the have an ant task equivalent of the "Create a release to associate with this build"?
Accepted answer
I am not aware of any kind of ant task - I checked - or other command line capability to do this. I am pretty sure you could create a Plain Java Client Library tool that creates the release and sets the build result to be a release. I don't have an example for this, but you could look into https://rsjazz.wordpress.com/2015/10/28/build-artifacts-publishing-and-automated-build-output-management-using-the-plain-java-client-libraries/ for some clues about the build API.
You can create an enhancement here: https://www.ibm.com/developerworks/rfe/
You can create an enhancement here: https://www.ibm.com/developerworks/rfe/