Here the 1841 British edition mixed up the word order, switching now it to it now. The 1849 LDS edition followed this secondary reading, but the 1852 LDS edition restored the original word order. As might be suspected, there are no actual instances in the text of “and it now came to pass”, but there are 105 of “and now it came to pass” (see the discussion under Alma 45:15). The critical text will follow the expected word order.
Summary: Maintain the normal word order for the phrase “and now it came to pass” in Helaman 11:1 and elsewhere in the text.