Describe the circumstances under which Sai Baba foretold the date of his Mahasamadhi.

The text from Chapter 42 suggests that the date of Baba's passing on Vijayadashami was fixed well in advance. Baba first introduced the idea by teaching that Dussehra is the auspicious moment for 'Seemollanghan,' or crossing the border of worldly existence. He then lived this teaching by choosing the next Dussehra, in the year 1918, as the moment to offer his body to the earth and merge with the Supreme. The narrative also connects this to a prophecy given to a gravely ill Ramchandra Patil. While reassuring Patil his life was saved, Baba foretold that Tatya would pass away on Vijayadashami in Shaka year 1840, the same day Baba himself would ultimately take Mahasamadhi, indicating his foreknowledge of this significant date.