QUOTE:-
Prisoners preparing for release
A prisoner may be asked to attend groups or courses to help them with any behaviour problems they may have, such as alcohol or drug abuse, gambling, financial pressures, depression, aggression or lack of temper control, or sexual matters.
Thus it would appear the pre-release program is solely to assist the prisoner not to assess their suitability to be released.
Pleased (I know you will) correct me if I am wrong.