The Satcharita says Baba 'left the body,' but also that he's beyond death. Can you explain what this means? Is he still present?

This is a profound concept explained in Chapter 43. The text clarifies that for a being like Sai Baba, who is described as the complete Supreme Brahman, the concepts of birth and death as we understand them are mere illusions. His physical body was just an adjunct, a temporary form he took for the protection and welfare of his devotees. When his task was complete, he didn't 'die' in the conventional sense but rather chose to merge himself back into his unmanifest, true form through the fire of Yoga. The Satcharita encourages devotees not to doubt his presence, stating that this beginningless and endless Sai remains unbroken and fills the entire moving and non-moving world in his true form. He continues to exist in the hearts of his devotees, and his influence is still felt today.