RE:Production CostsI can recommend to take part in their quarterly video conference discussing their quarterly financials and activities. You can address questions there directly to Cristiano and Felipe there.
Cristiano is also active from time to time on the ceo board. The ceo board can also be an alternative to SH to start discussions as it can be a bit quiet here from time to time. They also have a very informative YouTube channel for investors where they put up their latest video conferences with Q&A.
Good luck with your investing!