Well, the actual piece will most likely be an EU piece, despite the first season being written by George Lucas.
However, since the content of first season mostly will have G-Level status (obviously, it is
written by George after all
) as a source, there's not much in EU that will be able to override it ... past, present, or in the future.
Not even the movie novels are able to do that, even though they rank as 3rd in the canon list (see post further up).