I have Tricare too... I didn't have to do a supervised diet but that may be because I am Tricare North/Standard. I had my first consult June 13th and my surgery is set for August 9th.
What took so long is that at the consult, the surgeon/nurses are going to ask you to get labs done (to make sure you are physically able to withstand the beating your body is going to take from surgery and to make sure you are currently getting the nutrients you need) and see their nutritionist (because the diet after the surgery is graduated back into normal solid food from liquids over a 1 to 2 month time span and they need to know you understand that... also that you understand various problems that may arise if you don't get the nutrients that you need). Also, with Tricare you need to have a referral from a Psychologist the specializes in weight loss surgery (they basically determine if your expectations are realistic with the surgery, if you are emotionally stable to handle all the the changes, and to make sure you don't have any alcohol or drug addictions). After all that (assuming that your surgeon doesn't require any other classes), the surgeon's office needs to send in an insurance "package" with all of the classes, referral letters, and BMI in order to get approval from the insurance company. WLS is one of those surgeries that requires PRIOR approval and they won't cover it if it is just billed to the company after the fact without that approval. Tricare is quick with the approval but slow with sending out the proper documentation to make the approval official to the surgeon's office... mine took 2 days to approve but 2 weeks to get the documentation to my surgeon for the go ahead. PLUS you have to realize these surgeons are booked weeks in advance (and sometimes months in advance) for the surgery... I was lucky and there was a cancellation for two weeks after my surgeon got the approval.
I don't think 2 months of a wait is that bad... but I don't know of anyone that got their surgery in less than a month (and they were all self pay!!!).
Good luck at your consultation and keep us posted... And if you already knew all this information, sorry. I tend to go overboard and give waaaaaayyyy to much information sometimes.