Originally Posted by kyouray
Now I reread the sentence there isn't negative form so I'd rather understand as "Okada writes considering OVA as a 1st ep" which looks more relevant with what duckroll said. If anyone can confirm...
Based on what was written in the Q&A on the site, what he probably meant was that Okada wrote the TV story based on the OVA, treating the OVA as an episode in a longer series. It fits with their suggestion that they could continue the OVA separately in future. But for the TV series, it is "based on" the OVA as the original material, but it will be a complete story in its own right.
Edit: Other info that wasn't posted above, from the same source:
- Kazuko Nakajima is still handling the color design for the series.
- Hideharu Mori is composing the music, which means ryo isn't... too bad.
- Yusuke Yoshigaki and Hiroyuki Imaishi also worked with Mari Okada on the scripts, along with various other staff members in the team. They all contributed to the formation of the series.