As per
paragraph R186(w), graduates who apply for a work permit, such as a post-graduation work permit, before the expiry of their study permit are eligible to work full time without a work permit while waiting for a decision on their application if all of the following apply:
- They are or were the holders of a valid study permit at the time of the post-graduation work permit application.
- They have completed their program of study.
- They met the requirements for working off campus without a work permit under paragraph R186(v) (that is, they were a full-time student enrolled at a DLI in a post-secondary academic, vocational or professional training program of at least 8 months in duration that led to a degree, diploma or certificate).
- They did not exceed the allowable hours of work under paragraph R186(v).
Applicants remain eligible to work full time without a work permit while waiting for a decision on their application even after leaving and re-entering Canada.
Applicants must stop working as soon as they are notified by IRCC (for example, via their MyAccount, by email or by mailed letter) that their application for a work permit is refused.
Seehttps://www.canada.ca/en/immigration-refugees-citizenship/corporate/publications-manuals/operational-bulletins-manuals/temporary-residents/study-permits/post-graduation-work-permit-program/permit.html
A foreign national cannot work in Canada, unless they have a valid work authorization, such as a work permit or a PGWP.
Regulations R200(3)(e)(i) states as follows:
(3) An officer shall not issue a work permit to a foreign national if
(e) the foreign national has engaged in unauthorized study or work in Canada or has failed to comply with a condition of a previous permit or authorization unless
(i) a period of six months has elapsed since the cessation of the unauthorized work or study or failure to comply with a condition.
Based on your situation, if you fall under the above, you will have to evaluate. If you did work without authorization you are reportable, and should consult a licensed professional to evaluate your circumstances based on your individual facts and circumstances.