I assume you mean "Boston, MA" as your location by using "Beantown." In the US, no, the doctor can tell you day of, or even just make a call if they're nice about it. I've had others say "I'm not keeping most of my patients after xxx date." I've also shown up to an appointment to be told "he doesn't have a practice here for two months now."
There's no laws in the USA about that at all.
Sorry you're having to deal with this. I think you can work it out.