I would isolate the plant and get a picture to the grower pronto. Not a good look, and if it is spreading it is not likely to be cold damage from shipping. If it were my plant, I would treat it with Bayer 3-in-1 in hopes of knocking down a fungus, if that is what it is.
Good idea. My first instinct was cold damage too. It was in the 60s here when it arrived, but definitely cold have been damaged en route. However, yeah, it appears to be spreading. It was only on 3 leaves the other day and this morning it's on almost all.