Specialization codes.

Hi, I got Halo 4 on november 6th. It came with two extra specializations. Wetwork and Operater. I know that I didn’t get the rest of the specializations because i didn’t pre-order the game. I live in the UK. I heard that all specializations were available to people who bought the game before 15th November. I have completed wetwork and Operator. I AM NOW UNABLE TO LEVEL UP BECAUSE NO MORE SPECIALIZATIONS ARE AVAILABLE. How can I get the rest?