If you open the pill box during the light window, lights will indicate which pills you should take. There is no alarm/notification during the first half of the window, so do not worry about it waking you up.
If you have not opened the pill box by the light window's halfway point, an alarm will go off on the pill box for 1 minute. You will also receive a notification on your phone at this time.
If by the end of the light window you have not opened the pill box, an alarm will go off on the pill box for the last 2 minutes of that window.