I think the position that it's about specific code is not defendable. What if I delete the file and retype it as a coder (see Theseus)? Is this the same file that was in a former release? If I automatically code format it, so no character is at the same position as it was before? Is it the same file? The only thing that makes sense is considering releases as the particular thing that is licensed (with each source file being a considered a part of the release, not a part in the history of the file).