When Edwin of Deira returned to power in 617, Ceretic was expelled, supposedly due to complicity in the poisoning of Hilda's father, and his kingdom was annexed to the Kingdom of Northumbria. He is probably the Ceretic whose death is recorded in the Annales Cambriae in 616 (which should be corrected to 617 or soon afterwards).
Edwin of Deira regained control in 617, Ceretic was expelled due to alleged involvement in the poisoning of Hilda's father, and his kingdom was absorbed into Northumbria. He is likely the same Ceretic whose death is documented in the Annales Cambriae around 617 (or shortly thereafter).