My insurance will only allow one pap smear test a year and typically my doctor schedules my appointment for at least 366 days out to prevent any issues. However I was recently diagnosed with high grade dyslpasia as well, had a colposcopy a couple weeks later and a couple more weeks later a cold knife cone biopsy which is going to require some further treatment. My doctor's office manager spoke with my insurance to make sure they would cover all of my procedures before we moved on with everything and they agreed to cover all of the procedures. In your situation you may want to get on the phone to "negotiate" with the insurer or see if your doctor can talk them into the coverage. If you do not have any success I would highly recommend you just proceed with the pap test out of your own pocket. Its a good investment in your health and well being. And could very well save you a lot of time, heart ache, and money in the long run!
One thing my doctor has told me a couple times is that she hates how insurance companies basically determine what the patient can take or have done to them, whether that is what is recommended or not. Sometimes we just have to take things in our own hands and do what is best for us...not what the insurance company thinks is best!
Sorry that was kind of wordy but hopefully you were able to get something out of it! Best wishes!