the author been doing this for a while now, its on twitter, just follow them if you like it.
its just rarely anyone translate it and posting it like this.
Eeh really? I just got my english 8.5 volume one or two month ago.
and I think volume 11 was just released last march and the 11.5 was scheduled this September.
that's it unless what you mean silent is the fan translation scene, I mean its a licensed title and yes there is a lot of butchering...
should be, its monthly release if I am not wrong.
thing like this are probably just random idea and art work that the author draw but can hardly put into the main story. or just a way to fill the gap between the long release.