I'm not entirely sure but all I can think to do is to wipe the BlackBerry (BBSAK) or (JLCMDR) leaving you with no OS, download the latest OS from the Vodafone website, or look here if your looking for a leak, then delete the Vendor.xml file. Then run DM
From what I understand, this will delete the Vodafone-ness from the OS, Dont quote me on this i'm only young. You'll still get the Vodafone 'Splash' screen and all that but it should be alright from there, wait for someone else's take on it though