On Saturdays and Lunar Observance Days the evening meetings begin at 7:30 pm and are followed by a Dhamma talk.
On Lunar Observance Days, the four moon quarters, the schedule is open and the day is set aside for formal meditation and contemplation. After the 7:30pm evening meditation and Dhamma talk, there is usually an all night vigil with sitting and walking throughout the night. At midnight, a one hour question and answer tea break is held in the Dhamma Hall. Sitting and walking meditation continues after 1 am until 3 am when morning chanting begins. The day after the Lunar Observance Day is also set aside for rest and further practice.
As the scheduling for the Lunar Observance Day varies somewhat from the observable moon phases, check the Abhayagiri Calendar for exact dates. It is optional for overnight guests and visitors to attend the all night vigil.