10 But after iii days, Mechir xiv, an order was given of the same Emperor Julian, also of the Vicar Modestus, to Gerontius prefect, ordering all Bishops hitherto defeated by factions and exiled to return to their towns and provinces. Now this letter was published on the following day Mechir xv, while subsequently an edict also of the prefect Gerontius was published, by which the Bishop Athanasius was ordered to return to his Church. And xii days after the publication of this Edict Athanasius was seen at Alexandria, and entered the Church in the same month Mechir, xxvii day, so that there is from his flight which took place in the times of Syrianus and Hilary till his return, when Julianus....Mechir xxvii. He remained in the Church until Paophi xxvi, Coss. Mamertinus and Nevitta (Oct. 23, 362), viii whole months.
Source: Historia Acephala (New Advent)