Production is planned to start in Oct 2018.Chizzles,
Thank you for posting the news.
I just checked Korean local news papers and found breif schedule to open Sangdong mine. According to an article on KW News dated on 8-8-2016 their plans are:
Dec 2016 - Mar 2017: Construction documents and Building permit process
Mar 2017 - Sep 2018: Construction
Oct 2018 - : Mine production
GLTA