I have UHC through my employer. My surgeon submitted paperwork to UHC on 11/11, and I received approval on 11/24. Surgery is scheduled for 12/17. But your mileage may vary wildly! :-) I was given my surgery date after someone else cancelled, so I'm not sure if I would have made it in December otherwise.
Are you enrolled in the Bariatric Resource Services program through UHC/Optum? My employer required it, and we had last-minute confusion over whether or not I had to submit 5 years of weight history showing BMI >35. It put my approval in jeopardy for a day or so. I met the weight requirement, but producing records was the problem. It turns out that when I started the Bariatric program, the 5-year weight history was not a requirement under my employer's benefits, so I was "grandfathered" in.
Anyway, I hope that information helps.