Some effects (such as Favored Enemy, Turn Undead, etc) are dependent on the classifications of particular monsters. By my interpretation of the limitations on the Monster Manual's Werewolf (phrases such as "humanoid form only" or "wolf form only"), the Werewolf seems to encompass two or more potential creature classifications, with the label of the "hybrid form" left seemingly ambiguous.
The word usage in the Werewolf entry of the Monster Manual divides the lycanthrope's forms into Wolf, Humanoid, and Hybrid. This suggests that that the non-hybrid monster classes are Beast and Humanoid, respectively. But what monster type is the Hybrid? My gut says that it could be a monstrosity, but it is still arguably a humanoid, beast, or combination thereof.
To clarify my intent, I have ruled in my game that Lycanthropes are bound by the laws of the moon and cannot change shape at will. For the sake of encounter building, this means that I must design a Balverine-Esque "permanently hybrid" variation of the Werewolf—read: one that is always in hybrid form and does not transform. Since it represents neither the human form nor the beast form of the traditional werewolf, I'm not sure how I should classify it.
What should I rule the hybrid when I run it in my game? Is there a definitive answer to this question?