Vasek 2013 Sri Lanka
Vesākha Wesak or Vesak also known as Buddha Purnima is a holy day observed traditionally by Buddhists in Sri Lanka, Tibet, Bangladesh, Bhutan, India, Nepal and the South East Asian countries of Singapore, Vietnam, Thailand, Cambodia, Laos, Malaysia, Myanmar, the Philippines, and Indonesia. Sometimes informally called "Buddha's Birthday", it actually commemorates the birth, enlightenment (nirvāna), and death (Parinirvāna) of Gautama Buddha.
The exact date of Vesākha varies according to the various lunar calendars used in different traditions. In Theravada countries following the Buddhist calendar, it falls on a full moon Uposatha day, typically in the 5th or 6th lunar month. Vesākha Day in China and Korea is on the eighth of the fourth month in the Chinese lunar calendar. The date varies from year to year in the Western Gregorian calendar, but usually falls in April or May. In leap years Vesākha is celebrated in June.
NEPAL: Buddha Jayanti == The name of the observance is derived from the Pali term vesākha or Sanskrit vaiśākha, which is the name of the lunar month falling in April–May (see Vaisakha). In Mahayana Buddhist traditions, the holiday is known by its Sanskrit name and derived variants of it. Local renditions of the name vary by language, including: NEPAL: Buddha Purnima (Budhha JAyanti)
always poor postmarks in Sri Lanka even in bigger PO