Comment 4 for bug 1564513

"Adding a trusty task to the bug" is correct; each row in the table is a task. But this issue is specifically about series targeting.

A project or distribution's driver can target bugs to series, and additionally a package's uploaders can too. This limitation is worked around in the Ubuntu case with the https://launchpad.net/~ubuntu-release-nominators team, which is a member of ~ubuntu-drivers.