Probably too late for the K-Meta, or at least its original intent of killing the wild yeast. You do it prior to adding your commercial yeast so there's no competition for yours, be it yeast or other. Now many on here (me included) recommend adding it every other racking to stave off oxidation. But there's no point to add it to an active primary.
The pectic enzyme can still be added, so go for it.
Meads: Hababero and Sarrano Capiscumel, Show Mead possibly getting split and flavored, and 12 gallons of Bochet Deliciousness
Ciders:3 Ciders with differing additives TBD, Strawberry/Apple Cider
Wine: Black Cherry Vanilla Port