Default Splash screen

I own a 16gb/2gbram UK device that I bought on ebay. My device is unlocked to any network out of the box but is a 3UK device and has a 3UK splash screen. Whatever generic kdz I install, my 3UK splashscreen remains.
On other devices I have owned, if I flash a generic rom I end up with a generic splash screen. My question is, if I root my device and change the splash screen to a generic one then return to stock using a generic kdz, would my generic splash screen remain?

EDIT Solved. Information required is in this thread: