O is the letter for today’s Saint. This gives us our saint, Saint Opportuna of Montreuil:
Saint Opportuna of Montreuil (died 770) was a French Benedictine nun and abbess. A Vita et miracula Sanctae Opportunae was written within a century of her death (ca 885-88) by St. Adalhelm (later rendered Adelin), bishop of Séez, who believed he owed his life and his see to Opportuna.
More can be learned about her at her wiki, found here.
St. Opportuna
Donal Graeme 
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