In 1909, during the Simchas Torah farbrengen, the Rebbe Rashab wanted to teach-say the Kuntres Ha’Avoda but because he didn’t feel well, he didn’t do that. Instead he published it in 1910. The Rashab was sitting during the farbrengen in the exact location where they did the Tahara on his father, the Rebbe Mahrash’s holy body. This caused him to speak about his father and say things Chasidim never heard before. See Zikoron L’Bnei Yisrael, pp. 22-23.