By following their Twitter account, found out that they were working on the OP portion, and then afureko work:
OP storyboards:
http://twitter.com/#!/AKB0048_anime/...598595/photo/1
http://twitter.com/#!/AKB0048_anime/...336576/photo/1
Afureko sessions:
http://twitter.com/#!/AKB0048_anime/...598144/photo/1
BTW, hope that gastroenteritis thing goes away so that Mayuyu can get back in and wear Chieri's shoes again.