So I'd love to understand this a bit more... Why would you do both? From my experience and from what I understand the PPF is self healing. Sure you want to Clay it before butting it on, but full paint correction isn't necessary (its a personal preference) and then subsequently, the Ceramic Coating really will just provide ease of cleaning, but no further protection than the PPF already provides.
I'm told, and no I haven't done it, you could scotchbright the PPF put it in the sun for a few hours and away it will go. My dealer even went as far to say properly installed PPF can actually hide existing swirl/minor scratches etc in the clear coat on the paint. The Ceramic Coating won't prevent scratches or anything, but it will look shiny and clean easier. The PPF is full UV protection too.
Just thinking out loud, not saying ceramic is good or bad or PPF is good or bad, but for the prices folks charge for some of these things, it makes me think twice...