August is typically vacation month (like the entire month!) for T's, and I think many pdocs, once you are on the same med schedule, do just see you every 3 months. Then there may be back-to-school rush? I know if I cancel my pdoc (at uni hosp), it means a delay of at least a few weeks. Can you at least get your refills? If not, I would call back and ask them to squeeze you in. Good luck.