If you want to limit req pressure ratio that is what KFLDHBN is for.
That doesn't establish a fixed absolute limit, only a pressure ratio. There is no other safety to prevent the set point to go over the sensor limit (one of the most strict no-nos in control systems - one that when ignored, actually has historically killed people).
Furthermore, it will never request 2559 mbar because of stuff like KFPRG and other things in the VE model.
Try it. It is quite easy to exceed the sensor limit.