According to Collider, end credits are going to be:
"Screenplay by Chris Terrio and JJ Abrams
Story by Derek Connolly, Colin Trevorrow, Chris Terrio and JJ Abrams"
George Lucas would then only be mentioned as creator of the character/universe. I would have liked him to be mentioned as "Story by", though if it was the case, it would likely have been on the poster.