Will existing AppleCare plans be replaced by AppleCare One subscription?

In the time it took me to type my question here, my "Subscriptions" updated and only shows the AppleCare One subscription. So, "Never Mind" (think Gilda Radner as you read that.)

[Re-Titled by Moderator]

Original Title: With existing AppleCare plans on my items, what happens to those existing plans once I join AppleCare One?