I had forgotten her comment about biting an ear off. That may suggest they're accelerating that story line to the LS reveal. Seems weird to me, though, when they could mine her story the way they have with the Hound and Arya, inventing interactions and extending that material over a whole season.
From a story telling perspective, it seems like having LS hanging someone (or several someones) who actually caused her family harm, would be a more satisfying sequence that would elevate excitement for the following season, than having her threaten and torment someone the audience knows is loyal to Cat.
And based on how D&D have been structuring this season, with a few cheesy inventions (I think we're about to get one of the cheesiest in the next episode) that lean heavily on making the audience think something good is about to happen, to not pay that off yet again, at the end of this season, would be more than groan inducing.
That is why I believe the LS payoff will be her ordering the hanging of Frey men. Granted, they could structure the sequence in such a way that it is essentially a "happy" reunion where no threats are made.