Root Removal of AT&T boot screen?

Hi all. I'm working with Firefly 2.1 which I'm loving so far (gotta get used to the up and down 3D style apps gallery) but I'm still seeing the AT&T World Phone white splash screen when I start up my phone (the very first screen I see).

Is there any simple way to get rid of this or perhaps replace it with a screen of my own?

Thanks all!:)