Can you explain the context of the Holi festival and the arrival of Sai's portrait as detailed in this chapter?

In Chapter 41, the arrival of Sai's portrait on Holi is presented as the fulfillment of a divine promise. The narrator had experienced a dream in which Sai Baba told him, "On a Holi festival day, I am coming to your house for a meal today." The chapter then explains the miracle of how this came to be. Just as the narrator and others were about to sit down for their Holi lunch, a man named Alli Mohammed arrived unexpectedly. As detailed in this part of the Satcharitra, he brought with him a physical portrait of Sai Baba, thus fulfilling the dream's prophecy at the exact right time and delighting everyone present.