I read that Sai Baba slept on a wooden plank. Why was this plank given to him and how did he end up using it?

As detailed in Chapter 0, the Masjid where Maharaj resided was in a dilapidated state, with a dusty floor and mud falling from the ceiling. A devotee, Nanasaheb Dengle, concerned about these conditions, brought a thick wooden plank for Maharaj. His intention was for Baba to place it on the ground and have a cleaner surface to sleep on. However, Maharaj used the plank in a very different and unexpected manner. Instead of placing it on the ground, he hung it from the rafters of the Masjid using old rags and began sleeping on it there.