How do you go from manual payments to automatic subscriptions?

I recently had a customers site go down from lack of payment even though there was a PayPal subscription in place. I had initially set the site to Pro status to demonstrate the capabilities of the site. The customer liked it and put in the credit card information to start the subscription. I went to work on the site and noticed it was not appearing and the link to renew the subscription was showing. I investigated the account and noticed in the history that an email was sent to remind the user to cancel the manual subscription...

Unfortunately, since I haven't got a response in a couple days on the previous thread I started on this subject, I was forced to cancel my client's automatic subscription, manually extend it to the date he has purchased through. He will have to enter his credit card information again and in 1 month I am going to run into this problem again. How do I make sure manual subscriptions are cancelled before the first automatic billing?