Vap Poya commemorates many religious events including the appointing of Sariputta Maha Thera as the Chief Disciple of the Buddha, the future Buddha to be Maitriya Bodhisattva's entering the Bhikkusasana, King RHO Vap Poya This public holiday in Sri Lanka takes place on the full moon day of Vap, the seventh month in the Sinhalese calendar. It usually falls in October in Vap Full Moon Poya, today Sri Lanka Mirror Right to Know. Power to Change Vap Poya The Month of Robes Tourslanka