Sorry for using local nomenclature the Pig Chair appears as "Easy Street" on the Ski Acres (oops, Summit Central) trail map. It is the fixed-grip double directly adjacent to the Pig Pen (oops, the PowderPigs ski school building) and is used all but exclusively by that school, Wednesdays through Sundays.
The story, as I've heard it, is that the Pig Chair received some nice electrical upgrades this summer (it also got a new base lift shack) and this work requires the lift be inspected and tested before it can operate. Hopefully this will happen soon--Pigs stand to lose 1/3 to 1/2 the season's use of this chair.
Alternatively, they can operate the lights only on the Pig Chair and load the piggies up the hill on Reggie's (sometimes known as the Condo Chair, because it's right in front of the Edelweiss condo building). This requires a bit of a death march from the Pig Pen, and most folks don't prefer to death-march their piggies if they can avoid it.
I'm heading up the hill tonight, will post if there's any news.