Emmy-nominated Stockard Channing, who until now has been billed as a guest star in her recurring role as the first lady Dr. Abby Bartlet on NBC’s “The West Wing,” has signed on as a regular on the drama series, reports Variety. The Radcliffe-educated actress, 57, has concluded a deal for 12 episodes this season, followed by at least three more seasons, says the trade paper. Meanwhile, “Wing” co-stars Allison Janney, Richard Schiff, Bradley Whitford and John Spencer showed up as scheduled on Monday to begin work on the show’s upcoming third season, averting a potential showdown with producers over how much they are paid. A lawyer hired by the quartet had hinted that the performers would skip the first day of production unless their salary demands were met, Variety reported last week. But Reuters reports that all four performers arrived on time Monday. Renegotiations of their original contracts are expected to continue. It has been reported that they each receive $30,000 per episode and are now seeking a triple pay hike.