I purchased Halo 4 at launch date, and I played Halo 4 on Xbox live November 11 (before Nov 20th) however I never received a code for the other specializations in order to rank up. I am currently stuck at level 70 and I cannot progress any further unless I have the other specializations. I appreciate the time reading this and I hope to hear back from you ASAP.
Specialization codes have been distributed. For more information on the distribution process, check this post