https://patchwork.openembedded.org/series/4459/ has been superseded by a V2 that wasn't detected (I'll file a bug for that). However to mark it as superseded I need to click through to each patch and set the state manually. Being able to select all and change state from the series view would be good.
Changes to add the requested functionality were sent to the Yocto mailing list for review and can be seen at https://lists.yoctoproject.org/pipermail/yocto/2017-February/034816.html https://lists.yoctoproject.org/pipermail/yocto/2017-February/034818.html https://lists.yoctoproject.org/pipermail/yocto/2017-February/034817.html and are also being tested at the staging instance: https://patchwork-staging.openembedded.org/
These changes are implemented in OE-patchwork: https://patchwork.openembedded.org/