It will end the call with you, and if the issue's not resolved, when you call back in it picks back up where you left off and immediately dumps you to a human. It also knows if there's a possible signal-related issue with your equipment based on things like CMTS alarms, and will also kick you right over to an agent to get it scheduled for a truck roll.
Oddly, the time I really needed the human (I had a cable modem for data and a cable modem elsewhere in my home wiring for the home phone system and the provisioning was screwed up and voice was nowhere at all) I was able to get them, explain the issue at hand, offer the data they needed, and got the call fixed and both modems reprovisioned and online correctly in a record 7 minutes.