Re: BF3 back to karkand missing?

I see on your Battlelog that you do in fact have Back to Karkand.  Try running a "repair game" on Battlefield 3.  After the repair is done, please REBOOT your PC.  Try loading into a match again that has either only Back To Karkand maps on it, or a mix of B2K and Base game maps.

They have since changed the coding on the base game to include B2K, so you don't need the expansion anymore.  When I re-download the game (I have Premium also), the B2K DLC never pops up in my current downloads, as it has been added to the base game, so when that downloads, I already have B2K downloaded as well.