Every restart there is a "roll of the dice", to determine where the location for field/processors/cartels. In the case of fields/processors, its more so a "flip of the coin" since there are only 2 locations for them (east and west). D2 refers to the second position for most/all fields and processors (correct me if I am wrong on that @Gnashes).
Just like a coin, the outcome once it is flipped is random, and can so happen to have 3, 4, or even 5 times in a row where it lands on heads/tails.