Sorry for the MC Hammer reference. Go search for "Hammer Time" videos if you don't know what I mean.
The shell host will be going down for a reboot tonight at around midnight tonight, GMT/UTC. That is to say, approximately 12am on Thursday Morning, 28th June.
This will be to switch to the latest released el6 kernel, and ensure recently update binaries are being used. If anyone has any background processes they will of course be terminated, and you'll need to restart them or ensure you have an appropriate crontab entry to start them. Post in the forums if you have any questions!