Review the actual documents and applicable process rather than relying only on an assurance.
Resolve the factual gaps
Identify current employer terms, qualifications and relevant history. A promised start date does not establish permission to begin work.
If the file is not ready, returning to Canada and completing preparation there is a legitimate outcome rather than a setback, particularly for a Canadian citizen who may later seek TN admission at a port of entry. Allow time to obtain an employer letter, resolve credential questions, and decide whether the case will be presented during border inspection or through a USCIS petition. The frequent mistake is booking a handoff and travel before the employer has finalized duties, leaving the applicant to reconcile a changed job at the last moment. Build a two-step timeline rather than a single date: a milestone for the consular appointment, a second for expected issuance, and a buffer before the intended admission and start date. If a start date is already fixed, raise that constraint with counsel immediately so the sequence can be planned around it, rather than assuming the letter can be fixed in transit.