The fact our Characters are basically uploaded in their database and we have to connect to their services to even see our characters, leads me to believe the characters would carry over. I imagine there will be yet another "character conversion" of sorts like what we all had to do with cutting off last gen consoles. Except, we'll be cutting off from D1 specifically and leaving that "instance" of our characters behind. I dunno, just my random thoughts of it.. ¯\_(ツ)_/¯