So I found the Folder Management page through My FA > Page Management > Gallery Folders, which allows me to create folders and folder groups, but how do I efficiently assign my thousands of existing submissions into the folders I've created?

If I have to open up each submission and click "Change Info" then assign it to a folder from there then it's way too much work for me to sort my existing submissions into folders.

I need a way of batch assigning them through the gallery browsing interface.