I've been keeping an eye on it, and the only other site on it seems to be mangafire but they're only up to 15.5 as well. J.Novel Club seems to be the official translator and they're only up to volume 3 chapter 15 while the raw Japanese is at volume 5. Translators both fan and officially paid...
So sad to see this axed, it was one of my favorites to read. Oh well at least it got an ending rather than being put in hiatus indefinitely or just abandoned which is one in the same
A shame this was canned I was enjoying it a lot, "Isekai Kokka Alchimaira" is similar but I find this one to be much more interesting and unique, if I could I would can that one and revive this one