What if it's going to be a piano-driven score? I believe it was a popular instrument back then too and Williams might want to write something fresh instead of his typical horn + trumpet Americana.
Oh, those fresh piano driven Williams scores...
I'd like to keep him away from those somber dramas for a while. The musical palette is so predictable, the already mentioned honored colleague from whatever soloistic department included.
After 50 years in the business, Williams has become predictable to certain extent (not only in somber dramas, but especially in his adventure scores - vide KotCS). I see no reason, however, to discard his upcoming score when there is not a single note written so far.