What happened to Sai Baba after he left his physical body, and how is it possible for devotees to still feel his presence?

Chapter 43 explains that after Baba's 'task for the devotees is over,' he did not perish but consciously left his body, burning it in the 'fire of Yoga.' He then 'merged himself into the unmanifest' and took up residence 'in the hearts of the devotees.' His presence can still be felt because he is 'firmly imprinted' in their hearts, and he 'always keeps the devotees awake' from his unmanifest state. The text suggests that a devotee's experience of him is very personal, stating, 'Whatever the feeling in one's mind, such is the experience even today.' In essence, Baba's body did not perish; he became one with Brahman and now fills the entire world, making his presence accessible through devotion.