Turnitin now has a new URL turnitinuk.com. the old URL will no longer work, however, all existing assignments are available via the new URL. This change took place on 1st January 2016.
WebLearn has been updated to use this new URL so if you access Turnitin via WebLearn’s Assignments tool then you do not need to do anything so this notice is really only for people who access Turnitin directly.