One telling of the Phoebe story from the 1940s says that ads and the jingles got so popular before WWI that the railroad had to hire a model so that she could make public appearances. Mobs were reported at many stations during a tour, Binghamton was best documented in that article. It was the government's operating of the railroads under the guise of the USRA that put an end to the hard coal in Lackawanna fireboxes, as well as those of the other anthracite railroads. It was Lackawanna's p.r. director Art Baumgartner who initiated the idea of naming the new streamliner equipment after Phoebe Snow. White and Shoemaker loved the idea and went with it.
Eyewitness accounts of that still exist.
Many models were hired to portray Phoebe at various events in various eras, some simultaneously. I don't think it's possible to complile a complete list. She was hired at the insistance of Edison to portay Phoebe during the dedication of the m.u.s. I picked up Ms. Daley at her house to bring her to ride the Last Run of the Lackawanna M.U.s fantrip that Tri-State sponsored, and a wealth of memories flooded back. She even discounted the popular photo of the first run as a fraud.