A business assignment decision is separate from the applicable immigration permission.
Review the finalized assignment before starting
Confirm the actual terms and assess whether any material change affects the case or required process. Do not assume that either every address update requires the same action or that all changes can be ignored.
Treat the site decision as one commercial milestone, not as immigration permission. Before starting, compare the finalized employer, duties, duration, supervision, and location with the case that was prepared, then obtain advice if a material fact has changed. TN still requires Canadian or Mexican citizenship, a listed USMCA profession, that profession’s prescribed qualification, and prearranged US professional work without self-employment. Canadians generally request TN admission at a port of entry or have an employer submit Form I-129; neither occurs automatically when a scheduling email names a site. Preserve the final offer and any change analysis so the work start rests on the correct authorization.
Hypothetical example: An architect from Saint-David-de-Falardeau receives Friday confirmation of the facility where Monday design reviews will occur. She should compare that assignment with the employer letter, confirm the architecture duties and qualification evidence, and complete the applicable TN process before lawfully performing them. A travel booking or site badge proves business readiness, not lawful authority to begin US professional services.