No, there's no mistake; you get another rest day already! For the next four weeks, you'll have three rest days per week. While this might seem like an excessive amount of recovery time at first, you'll soon find that the more intense workouts in Phase 3 warrant it.
Feel free to take a walk or perform some other light cardio on these rest days, but don't go all-out. Muscle isn't made in the gym; it's made while you're relaxing, eating, and sleeping. Your body is doing what it needs to on these days, so enjoy the time off.