Evidently it took that long because they ran out of "parts" (the CS rep did not specify what kind of part or what for) to calibrate my lens so they had to order the parts and await for their arrival. I called on four separate occasions to receive status updates, but not in a rude or forceful way or anything like that - just to inquire.
JackProton, thanks I may do that after the holidays when I don't need my camera and lens as much.
-spam- it went to an authorized Sigma service center. I looked up the address and it's on their website;
Camera Repair Japan
3435 Breckinridge Blvd, Suite 130
Duluth, GA 30096