I was wondering how you will twist it, and it's just funny
Beelzebub was originally announced as Jump Festa event, so is BC. "This isn't the same case here where its just the event", you sure? Go read the first ANN link I provided and you will see that only the event was announced. Just imagine this: today is June 30th, 2010 and they just announced Beelzebub OVA for the Jump Festa = you would have been claiming the exact same thing as right now for BC, and you would have ended wrong. It's the exact same case for Beelzebub, Toriko, AC, etc Jump festa announcements = their first anime projects. Beelzebub needed 2 months to announce the tv anime, the other needed more. Your statement that BC will be like Toriko, AC = different studio for the TV anime is based on the lack of TV announcement with it. Which is just way too early "fact" statement as like I said Beelzebub was also announcement without TV at first.
You can continue twisting and choosing what to believe as much as you want, but the simple fact remains: Toriko, Beelzebub, AC, BC first anime projects were all announced only as jump event. And since Beelzebub later got TV too and with same studio, it destroys your "fact" for different studio. Also you can't be sure that Beelzebub's OVA was just for promotion for the TV, as usually its the opposite, to promote the TV, they announce an OVA. Like recent example: Drifters, they first announced the TV, then the OVA promotion. Also another thing, all those OVA's are made for promotion the upcoming (even if it's not announced) or eventual tv anime. They are there to spark the interest, to test the audience. So technically, they are all just promos for the anime and manga.