well, that's all up to you..
i usually update my diaries daily, so in that case even when the plants start flowering, i'm usually in the middle of a week, so i finish that one off as vegging, and once that week is over i start set the next one to flowering..
given it's only a few days it doesn't really matter either way.. and harvest should be based on trichome-color as well anyways (and not really amount of weeks)..