Update: The latest confirmed information about Prepon and Season 2 of Orange Is the New Black is that she will appear in four episodes. Read that story from Nov. 12 here.

Laura Prepon has gotten fantastic reviews for her portrayal of Alex in Orange Is the New Black — but she will not be a series regular in Season 2, according to sources close to the show.

Prepon will come back for a limited number of episodes in the show's 13-episode second season in order to resolve her story. And the door will be left often for her to return in the future. But the actress did not sign a contract tying her to the show for the upcoming season.

Fans will likely be disappointed not to see a years-long arc play out between Alex and Piper (Taylor Schilling); their troubled past relationship resulted in Piper's imprisonment, the main plot of the show. And their (sexual) dynamic, given the fraught circumstances, has been one of the first season's most thrilling threads.

Prepon is best known for her long run as Donna on Fox's That 70s Show. After it ended, she starred in ABC's October Road and NBC's Are You There, Chelsea?, both short-lived, among other things. One of her agents responded to an email by saying he could not discuss the show, and her publicist did not immediately answer an email asking why Prepon would leave Orange Is the New Black. Netflix did not comment.

Orange Is the New Black is the latest show, and some would say greatest show, in Netflix's ambitious foray into original series for its subscription service. It was created by Jenji Kohan (Weeds), and is based on a memoir by Piper Kerman. Kohan has taken many liberties with Kerman's real story, however — including the Piper and Alex characters reuniting in prison.

Since Netflix doesn't release numbers for its shows — a decision its competitors criticize — it's impossible to know how widely watched Orange Is the New Black is. But it certainly seems loved. For reference, here are two (of several) BuzzFeed posts singing its praises: 23 Surprising Facts "About Orange Is The New Black" and Why You Need To Stop What You're Doing And Watch "Orange Is The New Black."

Season 2 began filming in late July in New York and will premiere in 2014.