Do you want to know what type of tasks await you in the current season? It's as simple as opening the Stagecoach Races window and tap on the " Tasks" tab. On the right side of the window you will see the season tasks available for the current season. Tap on the task icon to find out its terms and conditions.
Note that the types of tasks do not change throughout the season (i.e. for four races), and will change when a new season starts.