The Intercession of the Theotokos
The Intercession of the Theotokos is held on October 1. Or the Protection of Our Most Holy Lady Theotokos and Ever-Virgin Mary. This event in the first decade of the month October is annual.
The Intercession of the Theotokos, or the Protection of Our Most Holy Lady Theotokos and Ever-Virgin Mary, is a feast of the Mother of God celebrated in the Eastern Orthodox and Byzantine Catholic Churches. The feast celebrates the protection afforded the faithful through the intercessions of the Theotokos.
Source: wikipedia.org