How long has the airline, that joined Mesa Air Group to found Henan Airlines, been a member of Star Alliance?
Henan Airlines:  Kunpeng was founded as a joint venture between Shenzhen Airlines of China and Mesa Air Group of the United States and was also the largest sino-foreign regional airline in China. Shenzhen Airlines:  It has been a member of Star Alliance since 2012, and is currently one of two Chinese airlines that is part of the global airline network.
since 2012