Offered a Position at a National University in North Japan

I shall name no names but you probably know which university this might be.

I am possibly the only english speaking faculty in the department and have been offered a position around a month ago.

Yet, I have not information on how much they shall pay me, what they need me to do, how long the contract shall be.

All my emails to possible colleagues go unanswered. The only person who does speak in a staff member running the office responsible for paperwork related stuff but he is apparently quitting so it shall be radio silence for a month.

I am due to start in about a month, luckily I am already in Japan and have a Professor Visa so no concerns there.

Is this usual for National Japanese Universities?