In Excession
During the events of Excession, the Grey Area pauses its historical research into a very comprehensive incident of genocide to help deliver Byr Genar-Hofoen to the GSV Sleeper Service. It travels within the Sleeper Service to the excession, and near the end of events appears to allow itself to crash into the energy grid near the excession and is presumed by the Culture to have been destroyed, though this is not the case, with the ship apparently having transcended some sort of boundary between universes or else having been assimilated into another consciousness.
Read more about this topic: GCU Grey Area