I'm speculating that the sudden appearance of Ferris' father had to do with Akiba becoming a regular district now, rather than the center of anime culture. Though the exact reason for the change lies entirely with Ferris' D-Mail that she sent back to the past, 10 years ago.
It could be that Ferris' loneliness about her father being absent in her life propelled her forward to create a moe culture in Akiba, but once her father returned there was no need, hence the change.
Christina's name is getting longer everyday.
