How log of a wait till surgery? Insurance hurdles

BC/BS of Minnesota, my insurance carrier, required a six-month waiting period.  It turned out to be a valuable time to prepare.  There was a monthly visit with a registered dietician at the local clinic who discussed how I was learning and applying new lifestyle habits.  The psyc eval was done locally, as well.  Having a BMI in the 60's, I lost over 80# during those six months.  There was no pre-requirement to lose any amount although it was mentioned the surgeon likes to see some pre-WLS loss to show effort on the patient's part. It also was mentioned that more you lose before WLS, the better surgery should go.  Talk about motivation!  

8 months for me.