When did people begin the Fast of Gedaliah before nightfall?

This source-based Torah study examines the question: When did people begin the Fast of Gedaliah before nightfall? It follows the canonical Hebrew discussion through the weekly portion and the classical sources cited there, preserving the distinctions and review status of the original. This localized layer is for study and discovery only; it is not a practical halakhic, medical, legal, safety or pastoral ruling.