I did read your post very carefully as I always do before I respond. My logic is if the appointment system is fully automatic, a spammer could fill all the spaces resulting in gaps in the schedule that the surgeon wouldn't be able to fill, thus the office must have some verification in order to ensure all of the the surgeries scheduled are legitimate. In addition, some people may want an earlier surgery date so if a window opens up, the office might look for people with flexibility in their schedule and move them from a latter date to an earlier date. A window farther out is easer to fill that one within a few days of the surgery date. It doesn't cost you anything to ask and if what I say is correct, it could give you an early surgical date. You are free to ignore my suggestions as I don't know everything but I am knowledgable about possible ways to work the system to your advantage.