DON'T PANIC! I was just signing in to post my good news and saw your post so I will respond to you first. I applied 3 weeks ago under family category ( my partner is a Kiwi) and I received the "approved in principle" letter back in 19 days!!! My file was quite complete, but I did not request expedited service or anything along those lines. You should be fine if you are not planning to leave until March. Take a breath-have faith. I think it's better, and faster to send a complete package that does not require wasting time with back and forth correspondence.
Good luck,
Mara