Wating for "Sopranos"

This may be best suited for the Cafe, but I think there may be a factual answer to my question.

There was an AP story today about ‘The Sopranos’ being picked up for a 6th season.

In the story it says:
Fans of “The Sopranos” have to wait, however. The series has been off the air since December and was widely expected to return in the fall. But HBO now says the fifth season won’t begin until March.

My question, why not start in December and why wait until March?

Surely the “Sopranos” does not take as long to make as say “Law and Order” or “CSI.”

I have no factual answer, but HBO has never really had a “set-in-stone” schedule for the Sopranos. It took over a year and half for season 4 to air!

Season 6 is rumored to be only 10 episodes instead of the usual 13.

MtM