Horayot 3: When a Majority Means Jews in the Land of Israel

Given that if the majority of Jewish people sin in following an erroneous ruling and they need to bring an offering to atone - who counts as that majority? It excludes the Jews who live in the Diaspora - with a source for that in the book of Kings. Also, how does this kind of majority obviate the views of the minority? And - a new mishnah! When the court issues an erroneous ruling and they realized they were in error and they correct themselves, but there are those who follow the initial ruling - do those people need to bring an offering or not? It will depend on their circumstances and whether they were in the position to hear about the revision to the ruling. Plus, what if the court wants to cancel an entire section of the Torah's law from practice?