My local Orange store have told me they WILL be carrying both the Black and White in both 32GB and 16GB. I have already pre-ordered a 32GB White from them.
The Orange Shop in Bluewater is one of the biggest in the country and they are NOT getting white on launch, did you part with money for your preorder? If you do get a white one, you sir, will be holding Excalibur, best of luck to you