Humana anyone

I was scheduled for my surgery prior to getting labs, psych and nutrionist. I have since completed all of these, I am waiting for the psych to get to the surgeon. I was scheduled for my suergery for Sept. 9, 2008. This was basically 4 weeks from my appointment to my surgery. I go for my ekg and final lab work 5 business days before my surgery and start my 2 week shake diet this Sunday. I asked my surgeons office if we are pushing it by scheduling so close and they said that Humana regualrly approves easily and within 3 or 4 days. I guess its that part of me does not want to start the shake diet to then be denied, delayed and have to prolong my time on the shake diet. Anyone with Humana experience?