I currently have WP DP 8.1 and updated today, but still says Black. What am I missing?
It's the CV UK rom, unlocked.
there is no fix for DP 8.1 yet to update to Cyan. You have to roll back. Best to make sure all your settings etc are backed up, then download the
Nokia Software Recovery Tool and flash your phone to official 8.1 with Cyan (I think this
is out for UK now).
Your current version number of your phone is listed bottom left (3051.40000.1347.1001) in the tool and the one you can download and flash on the right hand side. Make sure the newer one is available - otherwise it will be the same you already have. Once flashed you can recover everything except your media files.
I did this with my kids' Lumia 520s and it worked fine and is actually fairly quick. It will take some time to get all your settings and apps back (will run in the background). They are now on Cyan with DP8.1 plus latest updates.
Too bad Cyan is not available for US yet - otherwise I'd do exactly the same thing.