How many places

Virtually all programs did at least some of their interviews in Nov or Dec. I can't think of any program off the top of my head that only offered dates in Jan. But I only applied in the midwest, so there could be some east, west or south programs that only interview in Jan.

there are many programs that only offer interviews in january. the 6 programs I interviewed at in january did not offer any dates in nov/dec, and I know of a bunch that I didn't visit where the same is the case. it's true, though, that many of the midwest programs do their interviews in nov/dec.

in general, a good deal of east coast programs do most of their interviews in january. when i went through it all, i had a midwest roadtrip in nov/dec and then spent almost all of jan on the east coast.