[kh99]

In the admincp, go to Attachments > Attachment Storage Type, and you should have the option to move the files from one directory to another. But since you don't want to touch the existing attachments, you might be able to go to Settings > Options > Version Info and Other Untouchables and change File Atachment Path. Yes, it says not to change it, but I think that's because it's supposed to be managed through the Attachment menu I mentioned above. If this was your live site I'd be a little more worried about changing it without looking at all the code that uses it, but since it's a test site I think it's OK to try it.