I don't think it will be very different. Pupil Premium students as a whole, do not make the progress they are supposed to. Many are significantly behind their (non pupil-premium) peers. This is why teachers now have to keep a close eye on these students and use intervention methods to support them. It is also why there is extra funding available for them. Therefore, I doubt the full quota of PP places will be taken, even with the lower cut off score. There are some anomalies: I know of a girl who is of PP status because her mother is a single parent and a TA on a low wage. However, her mother has two degrees her daughter is very bright; her mother has done all she can to enable her to grow academically. She might benefit from the lower entry score, but will probably gain a score above the " official" cut off anyway.
One PP child I know scored 245+ so although he will be taking a PP place, his score would have been sufficient for a non PP place anyway.