From my Orthodox friend Alex Nikas, news of a calendrical expedience:
Greek Orthodox to Celebrate Saint George’s Day on April 29
The annual celebration of Saint George on April 23 is one of the most important feasts in the Orthodox calendar. Almost all Greek households have someone called Georgios or Georgia among close or distant relatives or friends.
However, this year Saint George’s day coincided with Holy Tuesday.
According to the Christian calendar, whenever April 23 is within Lent, and therefore during the fasting period, Saint George’s day is moved to immediately after Easter.
This year Georgios and Georgias all over Greece and abroad will celebrate their name day on Monday, April 29.
This happened in England in the year 2000, when Easter fell on April 23; the Church of England moved St. George’s Day to May 5 (I think). I can state authoritatively on the basis of my own research that the English royal court moved the feast of St. George in the late Middle Ages if it conflicted with Holy Week.