Google News & custom URLs

In order to qualify to be added to Google News, you must add a three-digit number to your URLs. I understand this can be done in the custom permalinks section. However, when I make the change, it alters all the past URLs as well as future URLs.

Is there a way to alter the URL structure without it effecting previous blog posts? I would like to change my URL structure only for new blog posts.

Thank you!