I know for me I went through all the same testing that you listed, Nutrition being the very last thing.
I met with my Nutritionist on that last visit and she sent my sign in form right over to my surgeons office so they can submit all my paper work to Aetna. Less then a week later I was denied because certain forms weren't submitted. That was back in April. We had to appeal the decision ... That lasted months ONLY because my surgeons office ended up being short handed and the person who handles all Lapband patients was out do to an illness. Before she was put out of work, she SAID she started my appeal. Apparently she didn't . Anyways, once the appeal was submitted, it took 21 days to get approved or denied. I was Approved October 28,2011 I believe Surgery was December 1,2011. I'm down almost 16 lbs. As of yesterday it's been 2 weeks .
It's normally pretty Fast. Also depends on how far out your surgeon is booked. I will also ask them how far they are booked. Good luck and keep us posted !