What do you do with an interrupted conversation?
A user can't really tell what state a conversation is in from looking at the text on the screen.
Does a user understand that this conversation had a specific state and it needs to be revived in that exact place? That isn't really how a conversation works with a human being.
You leave off. You might meet at the coffee pot. Their might be three separate emails.
What you return to doesn't have to be addressed as though it were some procedural checklist. The bot needs to be smart enough to remind the user, to help them pick up where they left off, or just move on if that is what needs to happen.
I work for Exadel, Inc. Exadel is a great company, with great people all around the world. I currently lead the Boulder, CO, USA office.