The reason for starting first with seven days for me is because so many times I've said "I'm done" and after one day drinking, then I go "eh... Nevermind" because forever seems impossible. Starting with first seven days seems less impossible... And gives a goal to,achieve and reap the reward, as it were. Totally a mental thing for me based on what I believe can work for me to gradually seek out change... One day at a time.