I am not sure when you have to establish. I switched in during my freshman year and had to state my concentration then. I really loved the program. Everything was very hands-on. I even got to make my own wine, even though I am the Wine Business concentration. Professors help out getting you a lot of great contacts as well, and all the wineries in the area love Cal Poly students. I personally think it is a great program. There are still some organizational issues since the program is fairly new, but we are getting a new department head this year which should help a lot.