I think once you get into the normal BMI range, you'll have to come off SS or SS+ and move onto 810.
Once you start eating carbs (step 3 I think) you'll start to replenish your glycogen stores in the liver which will mean some weight gain, but by maintaining a low calorie intake (1000 per day) you can stay the same weight or even continue to lose weight, albeit more slowly.
I'm on 810 at the moment and plan to move onto step 3 when I hit my target weight of 70kg. Can't wait- I'm 79kg now, hurry up and move fat!!! X