Can you provide the specific date, year, and time of Sai Baba's Mahasamadhi according to the Satcharitra?

Certainly. Chapter 42 of the Shri Sai Satcharitra provides detailed information about the timing of Sai Baba's passing. It states that Baba left his body in the Shaka year 1840, during the first month of the sun's southern transit (Dakshinayan). The specific day was Vijayadashami, which falls in the bright half of the month (Shukla Paksha). The text further notes that this coincided with the 9th day of the Muslim month, the eve of Moharram. As for the time of day, it is mentioned that Sainath made his preparations for departure in the third watch of the day.