Changed B/U location—moving files from old location?

From within ATHI, I changed the backup destination from a USB-connected external drive to a NAS devise. It’s saving new .tib files to the correct place, but left the originally created files on the external drive. To set the new destination, I clicked “edit backup settings” and then selected browse from the “destination” pane.

I’m awfully sorry if this is a RTFM or absurdly simple question, but from searching the forums (and miserably failing to find the answer in the manual) I’m seeing that things may be a bit more complicated than a simple Windows Explorer move.

Can I just drag and drop the .tib files to the new location?
Are there hidden files or anything else I should be aware of?
Are the old file locations stored within ATIH—and do I need to tell it where the files moved?

I’m in a Windows 7 environment; Acronis is version 12.

Thanks~