Maintenance time...

(mt) Media Temple will be applying an update (GMR v.1.1) to (mt) Media Temple’s (gs) Grid-Server system.
This maintenance action will involve several tested software updates, server configuration changes, and network configurations designed to improve the operations of the system.
Although it is not expected that the full maintenance window will be required, it is expected there will be a few brief periods of inaccessibility of services while the maintenance is conducted.

Take a look here to see what this update includes ;-)