BBC News Japan published an article titled 'フィリバスターとは？ 韓国国会で最長記録' (What is a filibuster? South Korea's National Assembly sets a record) on March 3, 2016.
Notes on verification
Multiple independent sources (YouTube metadata, Hatena bookmark aggregator) corroborate the exact title and BBC Japan as publisher, and the underlying event (record-length filibuster in South Korea's National Assembly) is well documented. However, the original BBC article page itself could not be directly accessed to verify date/byline firsthand.