It is a shame this had to occur, but... then just because someone is excellent at exploring and running a small cap does not mean they are the right person for the job at running a gold company in production.
Mike Dunbar has been pretty amazing to date, in how he has led the company etc. I think its important to note that there was no board friction etc, at least publicly. He has resigned, in the interests of all shareholders. He holds a lot shares and IMHO will keep holding.
The board and team in charge of GCY are now very experienced and have impressive histories. Hopefully they can proven their worth in the current quarter and hit commercial production as planned.