I doubt it, esp. given the low quantities produced. I suspect PiPs are interspersed w/regular Priuses and other cars on the same line. I posted about my visit to a (the?) Tsutsumi plant in late 03 at How 2010 Prius is made in Tsutsimi plant - Videos | PriusChat. There were plenty of other cars being produced w/models interspersed (e.g. Camry, Lexus ES (IIRC), Avensis, 2nd gen Prius, etc.)
Some of the stills from that slideshow are up on the Prius Facebook page btw. Prius team posted them back in March.