Board Thread:Questions and Answers/@comment-155600-20171107003734

I've seen a lot of fandom websites refer to Prometheus and the Daedalus class as BC-303 and BC-304 respectively, but I don't recall that designation ever being used in the show. Now that SGC is online, I've been rewatching the series' and i still haven't heard the BC prefix used. If they use the type designation at all, it seems like they call them X-303/304 or just 303/304. Where did the BC come from? 