I don't think it is common. The correct phrase, and what I've always heard, is "180 degrees", meaning "the opposite direction". I can imagine "360 degrees" be

I don't think it is common. The correct phrase, and what I've always heard, is "180 degrees", meaning "the opposite direction". I can imagine "360 degrees" being used by people who are bad at math or not thinking about it, though. In the article the author really means 360, though, because she's back where she started.