A single suite upgrade usable for one night only is contemptible. Right in line with the disdain with which Accor (at least in Europe) seems to treat its best customers.
My “normal” stay pattern at Fairmonts would get me at or close to Diamond, but I would certainly not make a push for it without knowing the benefits. I am also so disgusted with the service at my last Savoy stay that I am not sure I want to continue that stay pattern, or, indeed, throw any more money at Accor.