Do not assume that the offer or an existing TN admission authorizes it. Confirm the required steps and actual permission for the additional work first.
Use the intended start as a planning input
Record the commercial deadline without promising a government result. If an offer changes, review the real duties and employer rather than only changing the start date.
Coordinate the employer’s schedule with the permitted activity and completed immigration steps, and avoid relying on a recruiter’s informal assurance about entry. State surveying licensure and any required examination usually take longer than the immigration step, and a start date built around a field season leaves no slack. The passport must be in hand before travel is booked; the letter and credential evidence must match the passport that will actually be presented; the admission record must be checked once entry has happened.
Treat the term start date as fixed and everything else as movable, then place the intermediate deadlines behind it: contract executed, transcripts received, translation and any evaluation complete, travel arranged. Ordering official copies from an institution or professional order and arranging certified translation both take time that is difficult to compress, and neither should be squeezed against a start date already promised to an employer.