10 days notice via voicemail?!? No wonder you are angry. At least give people more notice and do it in writing. I wonder if something happened and she is no longer allowed to see patients?
That said, I'm going to play devil's advocate. I think y'all know I'm a therapist. I've known people who stopped seeing clients and only do supervision because they are just too worn out by the profession to see clients. Maybe something similar happed with your doc?