It's a bit complicated, but quite clearly a part-time person doesn't have to report and a full-time person does. There are some general provisions that apply to both sets of people--the general rules of conflict--but any of the rules around disclosures or divestments don't apply to part-time people.
One area where I wondered whether people were complying with the act is with the receipt of gifts, for example. I don't have a regular connection with part-time public office holders, and I thought if I at least sent an annual letter reminding them of their responsibilities, maybe they would remember. I have no way of knowing. Maybe they're all complying, but I have no idea.