We will be performing a minor Gerrit upgrade to version 2.13.12 tomorrow (January 18, 2019) at 1700UTC. We've tested this upgrade on our dev server, https://review-dev.openstack.org, and expect it to be a quick upgrade. Any outage shouldn't last more than 10 minutes. We will let our configuration management tooling manage the upgrade so we won't have an exact time, but will try to get it as close to 1700UTC as possible. Feel free to test out the new version on the dev server. We are happy to answer any questions you might have as well. Sorry for the short notice and the cross post, Clark