Typically on a PCU you will get a provisional qualification. During your initial quals, you will simulate everything you would normally perform and then you're officially qualified. Once the plant is up, you will have a certain amount of time (I'm not sure how long) during which you have to be observed actually performing everything, which is then signed on an addendum card. At least that's how it was done when I was on a PCU back in the 90's, that was also a carrier, not a sub.