Peace be upon you. Can a person who is obligated to fast break their fast when they are certain that sunset has occurred and the eastern redness has disappeared, according to any of the approved calendars (such as the one by Al-Saigh), or must they adhere to the calendar approved by the representative office of Imam Khamenei (may his shadow last)? In other words, is it sufficient for these calendars to align with the fatwa of the reference regarding the absence of redness, and is this difference merely a matter of identification and not binding on the individual?