The servers will stop processing jobs on 2022-04-15 at around 16:00 UTC, as the server will be put into "Shutdown mode".
This downtime is needed in order to upgrade Jenkins and some of its plugins.
As of 2.307, Jenkins will begin a naming migration to refer to the "master" node as "built-in". We have submitted updates to existing jobs that request "master" as the build node to add in the "built-in" label and will continue to support "master" as a label on the new server.
Start: 2022-04-16 12:00 UTC End: 2022-04-16 20:00 UTC