Please see the announcement below from TurnitinUSA about scheduled Turnitin maintenance time on Saturday 21 December. Being out of term time and close to Christmas, it should hopefully not affect use of Turnitin at Oxford University.
“Turnitin service may be intermittently unavailable during a scheduled maintenance period on Saturday, December 21st, 2013, from 7 to 11 AM U.S. Pacific Time (click for local time). An announcement will appear for users within Turnitin in advance of when the system will be unavailable for this scheduled maintenance.
Instructors are encouraged to modify assignment due dates either before or at least several hours after the scheduled maintenance window.
Thank you for working with us as we improve Turnitin.
The Turnitin Team