I'm kind of new to the berserk fandom and this could very well be a dumb question so forgive me in advance but nonetheless I have to ask, how do we know for certain it is an art exhibit? Like, all we have is the manga mogura twitter account saying it and the leaked image no name posted, but what are the sources of these images? I tried reverse image searching them and all I could find were twitter accounts reporting on it. I am not questioning the validity of these sources of course, but nonetheless I am curious.
Heiji, who has been a reliable source of information for leaked Berserk news for years, posted about it here. That's why we're talking about it with some authority. But we'll know all the details tomorrow, once 10/9 rolls around in Japan.