There seems to be a glitch where some services on the 350s PIS don't change when you are terminating and doing a return service. I don't think (off the top of my head) that you can manually change the destination on a 350 as its automated.
You can't change the destination screens on the class 350 or 390. It is all done automatically. And yes, I have noticed sometimes when doing a service to Birmingham, the train screens show the destination as Euston.
