I'm not sure specifically which 'Dave not coming back' true story you're referring to. There could be many stories with that title or concept. It could be about a person named Dave who left for some reason and isn't returning, perhaps due to a job opportunity elsewhere, a personal choice to start a new life in a different place, or maybe something more tragic like an accident or illness that prevented his return.
The 'dave not coming back story' might be about Dave who went on a journey or an adventure. During that time, he discovered new things and new places that made him not want to return. It could be that he found a new community where he felt more at home and decided to stay there instead of coming back.
One possible ending could be that Dave starts a new and successful life wherever he is and completely cuts off ties with his previous life. He may find new friends, a new career, and be content with his decision not to come back.
One possible ending is that Dave starts a new life completely and is very happy with his decision not to come back. He makes new friends, has a great job, and forgets about his old life.
I'm not aware of the specific comeback time of 'Based on a True Story'. Maybe it'll be announced soon on relevant entertainment platforms or in the media.