No. Operational readiness does not replace the required immigration permission.
Review the actual first duties
Training, delivery and preliminary tasks should be described accurately for assessment. A badge or system account is not an admission or work-authorization decision.
A Canadian citizen may apply for TN admission at a port of entry with the required evidence or have the U.S. employer file Form I-129, but approval within three weeks cannot be promised. A first review should create a dated sequence from the signed offer through the chosen admission or petition step, travel, and the first lawful workday. Begin with the planned start, worksite, admission procedure, licensing milestones, and the employer's real flexibility. An applicant who arranges the port-of-entry visit before the state licence issues may be admitted yet unable to work, or may be told by the employer that onboarding cannot begin. An employer's start date sets when the role is expected to begin; whether work may lawfully begin is decided by the authorization steps, and no filing or application permits work while it is pending.