from Upāli Thein, Bagan, Myanmar
Most sources are in agreement this year, but the Sri Lankan calendar from the Galdua group of Forest Monasteries (marked SL below), only makes the extra day adjustment (adhikavāra) on the 3rd Uposatha in Gimhāna, and is therefore one day in front till that time. There are also some small differences in the Dhammayut calendar, marked by DY below.
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