Workflow service may not be available during the normal maintenance window on 1/21/2014
On 1/21/2014, during the normal maintenance window of 5-7 AM we will be
performing some updates to the Enterprise Workflow service to implement
changes to the WTSR form. During this time, the Workflow service may not
Story added 20. January 2014, content source with full text you can find at link above.