My brother applied for a change of status and he got his priority date for November 2012. Since his H1-B visa was about to expire, he filed for extension right before he left the country, but was denied, and is still waiting for reasons. What can he do at this moment?
It appears that you have two questions: (1) about the November 2012 priority date and (2) a change of status (from H-1B) that was denied. In general, departure from the country after filing an application results in abandonment of the requested benefit. As for the priority date, it is unclear what questions you have. Your brother, who likely has more information about the case than you, should consult an experienced immigration attorney to discuss and analyze all issues in detail. It is only under such circumstances that a strategy or solution can be crafted.