How to migrate existing upload after activate W3 Total Cache

Hi,

I have an existing WP website with hundreds of images in the local wp-content/uploads/ folder. After I installed and activated W3 Total Cache plugin with Azure Block Storage as CDN. The wp-content/uploads/ has pointed to https://example.blob.core.windows.net/wordpress container. I can confirm all settings are correct and I can upload images to the Azrure BS container.

But all my existing images are still in my local folder. How can I migrate these images to the new Azure container location? Do you have to do this manually? Or W3 Total Cache can do the migration automatically?

Cheers,

Tao