An email address is your Identity; while it's possible for you to maintain the same chat when you migrate, you'll sever the chat for the other person because th

An email address is your Identity; while it's possible for you to maintain the same chat when you migrate, you'll sever the chat for the other person because they have to chat with a new Identity (your new email). (think the email headers to/from, you've kept "to" but changed "from" for them, but it could use the same PGP keys to decrypt etc.)