Can you explain the process and significance of Baba giving Udi to his devotees before they left Shirdi?

Chapter 33 of the Shri Sai Satcharita explains the established practice of Sai Baba giving Udi to devotees. When devotees would ask for his permission to leave Shirdi and return to their villages, Baba would give them Udi. The text highlights a special significance to this act, stating that when Baba said, "Take the Udi," it was understood as his true permission being granted for the journey. This act would fill the devotees with enthusiasm. Furthermore, giving Udi was not limited to departures; it was a daily ritual for all, happening in the mornings, afternoons, and evenings, ensuring no one left his presence empty-handed, symbolizing his constant blessings and protection.