I already pointed out above that there are two sources supporting the characterization of the company as "semi-professional":  First,  this article says that the company is "a professional nonprofit theater company".  The company's website says that some of the company's goals are to: 1. "Provide a showcase ... assisting in the advancement of professional careers; and 2. Provide training and performance opportunities for professionals and semi-professionals."  So, the conclusion that the company is at least "semi-professional" is amply supported under virtually any definition of "semi-professional" that you could find.