:You assume incorrectly that the author is unaware of this rather trivial detail. The change introduced under the Ptolemies (the so-called "Alexandrian calendar") represents a simple reform to the Egyptian calendar. The Coptic calendar is a direct continuation of the Egyptian calendar with the addition of Euergetes' leap day that was adopted later. That the Egyptian calendar prior to the Graeco-Roman period did not have that feature is entirely irrelevant to the simple statement I added, which I am now going to re-add with further additions to the article. Furthermore, the population at large, who is mostly Muslim, technically does not use the official Coptic calendar, whose dating begins with the Christian 'Era of the Martyrs'. That detail did not prevent you, however, from stating that that Coptic calendar is used by "the Egyptian populace in general". This is true only in the sense that the calendar used by Egyptian Muslims is a continuation of the Coptic calendar, in turn with roots in ancient Egypt. The agricultural calendar used by Egyptian farmers today is simply the Egyptian agricultural calendar, same Egyptian seasons, same Egyptian months. —  ·