Can you explain the 'exchange' that supposedly happened between Sai Baba and Tatya Patil on Vijayadashami?

The concept of the 'exchange' refers to the belief that Sai Baba gave his own life to save Tatya Patil. According to Chapter 42, Baba had precisely predicted the day of Tatya's death. On that day, Tatya was critically ill and near death, while Baba was also unwell. In a miraculous turn, Tatya's health improved and his life-danger passed. Simultaneously, Sai Baba left his physical body. The narrative explains that people interpreted this as a deliberate act by Baba, who gave 'the exchange of his own body for Tatya's death' to avert the prophecy for his devotee. This event is cited as an example of Baba's mysterious ways and profound compassion, a plan no one understood until after it happened.