Obviously as this your first tour it will be Herrick 1 for you, however for some in your unit it may be Herrick 2 or even 3. Don't worry though the BFPO number is the same whatever Herrick it is for you. And the days of the week remain the same for people on Herrick 1, 2, 3, 4, 5, 6 and so on. It just helps to avoid confusion. Hope this has helped.