It's common journalistic practice to have obits ready to go at a moments notice for any famous person. They do update them from time to time. You don't have to worry about yours ending with the date of your graduation from the Gymnasium.

Hell, yes, updating the obits was something that no journalist at my newspaper wanted to do. It was therefore deemed, in order to make the worst of a bad job, to be the job of the cub reporters who were at the bottom of the hierarchical journalistic league tables, and who had no one else to fob the task off on to.