American Living in China

I am an American citizen living in China. I plan to travel to Ghana this summer from China. I do not live in Beijing, but I will be traveling there for a week in late April. I will not have time to travel to Beijing later than April to get my visa. I am not scheduled to leave for Ghana until June. Will my Visa still be valid for use more than 30 days after it is issued so that I can get my visa in April and travel to Ghana in June?