Well hello there, ArcLight lobby. Long time no see. Two years, in fact. But the lights are on now, the boxes are being unpacked, the ArcLight signs have all been removed, and the AMC banners are being hoisted. The world’s largest movie theater chain has officially announced what we’ve all known for quite some time: It’s taking over the theater at Westfield Montgomery mall, and doors could be open by next month. In other welcome news: AMC’s frequent-viewer loyalty club, which gets you a dozen flicks a month for $21.95 plus tax, will be honored at this location.