Wait is Lugarugan's form permenant or is it interchangeable between night and day?

samazam said:

Wait is Lugarugan's form permenant or is it interchangeable between night and day?

"The name of the Pokémon Rockruff evolves into is Lugarugan and has a different appearance based on if it evolves in Day or in Night. It notes that Rockruff becomes the Midday Form when bathed in the rays of the sun and when full of the night's power, it becomes the Midnight Form. No types or further details have been given"
-Serebii.net

samazam said:

Wait is Lugarugan's form permanent or is it interchangeable between night and day?

Pretty sure it's permanent, the artist is just referencing how Espeon and Umbreon have that similar day/night motif evolution.

Oh okay then. Got confused since some sources states that its interchangeable. Guess sticking to Serebii and Serebii alone is wise huh?

samazam said:

Oh okay then. Got confused since some sources states that its interchangeable. Guess sticking to Serebii and Serebii alone is wise huh?

Serebii is a page where you normally don't find unconfirmed news and is normally professional.
So the quotation is all we have for now.