Jedris was an uninhabited planet in the Orthana system.
In the 53rd Segment of Time, the Eighth Doctor, the War Ollistra, Bliss, Quarren, and Rupa all escaped to Jedris while fleeing the Daleks. The planet's temporal relationship with the rest of the universe was altered by the Time Lords so that time progressed much more quickly here. This was done to stop the Daleks from capturing the powerful Time Lord, Quarren. (AUDIO: One Life)