Idk about 30 or even 60 days. if you look at this review taken on feb 17th, on the last paragraph Todd stated that the dlc is very early in development. My thought that the DLC wouldve been released in May just got pushed back to November. Past DLCs like Bloodmoon and Shivering Isles took a year to make. However are they going to do the large stuff or small stuff first thats the question?
http://kotaku.com/5885983/bethesda-skyrim-dlc-will-feel-more-like-expansion-packs
DLCs usually start coming out 6 months after initial release, that would be 60 or so days from now. This based on FO3, Oblivion and New Vegas. Bloodmoon and Shivering Isles were Expansions, practically full games on their own. Well, Shivering Isles was certainly like a stand alone. I do know they said the DLCs would be more substantial, but would that apply to all of them?