The above AIT website states that :
I emailed them last week and this is the response that I gotFor appeals against an entry clearance officer´s decision, you need to use the appeal Form AIT 2 which is issued to you by the embassy or British High Commission when your application is refused. Form AIT 2 is here for information only.
Our ref: BH
Dear Sir/Madam
Thank you for your email.
You can download the AIT 2 and send it to us we will accept it.
Regards
Email Customer Enquiry Unit.
Therefore you can download the form from their website and use it to appeal, contrary to what it says on their website
Hope this clears the matter up