This is something we try not to make public sorry Luke - the automatic validations are many, numerous and change on a regular basis, based on legal advice, legislative change, legal challenges, identity / validation etc.
There is then an ever larger tier of rejection reasons based on our business rules - a fair number of submissions are referred to query handler colleagues if the automatic validation decides further examination is required, and this is when these business rules kick in. The examiners also have free text boxes to use if required.
The presenter would generally not know whether the rejection was automatic or query handler related, although automatic validation rejections would usually be returned quicker.
SDN