Will changing the date and time in Nintendo DS affect save data
Changing the clock on the DS will change the clock in-game, and it won't mess up your save. However, your plan still won't work as well as you expect. Whenever you change the time on your DS, you can't do any time-based events for 24 hours after you start your game again. Thus, feel free to change the time to better fit your schedule, but don't expect anything until a day after the change.