My BMI was 31 it is now 30. I had the lap-band for 12 years and stayed at my goal weight nearly the entire time. Lap band was super effective. Unfortunately it slipped and it was removed.
Fast forward a year and 40 lb. gain, I had gastric sleeve surgery beginning of June. It's October 1 and I've lost 19 lbs. 10 lbs. was lost in the 1st week.
Even with proper diet and steady exercise, don't expect the weight to fly off.