We're currently keeping history of the unittests results by feeding he xml files to the "Publish Junit test report result" plugin.

However, we'd like to know for how long, or when a test started to fail, hence we setup the tests stability plugin.

The issue is that the tests stability plugin is only aware of the current tests result.
Could this be a bug?
Something not properly configured on our side?

You can get an idea of what I'm talking about on any of the builder on:

http://jenkins.saltstack.com/

And, as an example, specifically:

http://jenkins.saltstack.com/job/salt-rs-arch/1159/testReport/