Why did BiBi change their center in their live shows for the song Love Novels?


According to [Wikia](http://love-live.wikia.com/wiki/Love_Novels), the
original Love Novels has Ayase Eri as the center, but it was replaced by Nico
in the live shows.

![Love Novels Wikia Screenshot](https://i.stack.imgur.com/TsO9nl.png)

Has it been disclosed why this was the case? What is the reason behind the
change?

