This definitely appears to be a real promotional image of some kind.
It sucks to see that Kylo will be wearing the mask again at some point. I’m going to assume (see: hope) it will be in a very limited capacity. It was already done to great effect in TFA, but that’s over now and the mask serves little purpose going forward. JJ would be a complete idiot to hide the face of his lead actor behind a mask again for half the movie.