Once the decision has been made and they have granted pr/Copr, it can not be revoked, I tell you why, before getting the visa/Copr you are just an applicant who has applied to be a Permanent resident, once they have concluded and granted one a Copr /pr, one has same rights of Permanent resident as someone residing in Canada, hence they can not just take it away, it has a long process on other party/spouse part to get it revoked. It is from a personal experience as someone in the family came to the point where they wanted ones application withdrawn, but it was too late since the decision had been made and they had granted the copr to them. Withdrawal is possible before them granting the visa to travel.
P. S, all this happened within 3 months. We did everything we could to stop the person but immigration said, the person has the rights of permanent resident hence they can not just simply revoke everything.
Regards