Sankashti Chaturthi

Every question on the site tagged Sankashti Chaturthi, each answered from a timestamped source rather than a summary written from memory.

24 Feb: The tithi began and ended without ever falling at moonrise (kshaya); the day it ends on is kept.

Computed for New Delhi. Sunrise decides which tithi a day belongs to, so these can differ elsewhere.

Festival
Saṅkaṣṭī Caturthī

A fast for Ganesha on the fourth lunar day of the dark fortnight (Krishna Chaturthi), broken after seeing the moon, and kept on the day the Chaturthi holds at moonrise.