ITS NOT THE DATE YOU WERE REFUSED WHICH IS THE DATE ON THE REFUSAL NOTICE.Its when the refusal notice was handed over to your wife when she went to collect passport ( 25th September, you have stated somewhere).
In Pakistan the refusal notice can be handed over to you sometimes as much as 3 weeks after you are refused
So you count 28 calendar days from the date she was handed the notice at Fedex
You have to get your Appeal Notice lodged within the 28 days either at the BHC post where you were refused ( can take 5 days in post to get to Pakistan).
If you cant get it in there on time, then its best you post it to AIT in the UK.
Remember if you dont appeal on time, your chances are gone and you will have no alternative but to reapply again.
If you dont have all the documents ready to send off with appeal, dont worry, you can send them a few weeks later.
Hope this helps, so if I was you I would start thinking how you are going to prove the ECO wrong in what he said in refusal.