This happened to my great grandmother (GGM) sometime in the 1930s. Back then, it was a common practice among those who lived in Indian villages to bathe at the village river. My GGM was no different. She would rise at the crack of the dawn, usually signified by the crowing of the rooster, and then walk down to the village riverbank with her friends for a bath.
One day, it was business as usual for GGM, but as she left home to go to the riverbank, she saw her friends weren't around. Assuming they were late, she continued on her way, though she did find it darker as usual. Once she reached the riverbank, she saw there was no one around except for one lady bathing in the river. She realized she was probably too early and decided to go back home. As she turned, the lady in the river called out to her and said that they were a little early, but since they were at the river, they might as well have a bath and others would be coming in soon.
Soon, my GGM struck up a conversation with her and asked what her name was and how long she had been there in the river. The lady replied with her name and said she entered the river a few minutes after she saw my GGM walking down towards it. My GGM was surprised, as she hadn't seen anyone on her way to the river, but casually, dismissing the thought, she asked the lady where she stayed. And, that's when she pointed to one of the trees at the river bank and laughed and started floating above the water. My GGM just gathered all her stuff from the bank and ran away, praying, never looking back. By the time she was back home, everyone was up, looking for her. It was only then they realized that she was out at around 2 or 3 am instead of the usual 4.30am that she used to go out.