The information is all available online:
http://www.ontario.ca/driving-and-roads ... rit-points
Perhaps he has another conviction he didn't tell you about?
When I read about the escalating sanctions, there was a note from which I understood that once a suspension is put in place, demerits are erased; perhaps the officer was thinking of this...its a stretch I know.
I have never hear of a case being reopened for not being aware of all the ramifications of a guilty plea, as great as it might be for some.