GASTRIC BYPASS REVISION Q'S

Anyone have to have a revision of a gastric bypass by getting a lapband?  My pouch is "huge" as per the radiologist who did the G.I. series and the bariatric surgeon.  My insurance company, United Health Care/Oxord says my BMI is too low, but it's not the original surgery and the BMI shouldn't  be included - or so I thought.  Anyone have a similar situation??