Complex sentence: In some cases recently new owners have renamed various mains "manor" in ignorance of the distinction in Scotland, and there are also occasional instances of the media using the tautology, "Mains of X farm".
Split into simpler sentences: In some cases, new owners have renamed various mains, "manor" in ignorance of the distinction in Scotland. There are also occasional instances of the media using the tautology, "Mains of X farm".