Review the revised assignment before relying on the earlier TN plan. The original professional description does not automatically cover materially different duties.
Use the assignment that will actually begin
Keep the employer’s changes and current responsibilities in the record. Identify whether qualifying geological work remains rather than retaining a title to conceal the change. A project delivery date does not grant admission, extend status or authorize activities outside the arrangement assessed through the appropriate process.
If the engagement is expected to continue past it, start gathering the employer's updated letter and any refreshed evidence weeks ahead, since collecting documents from a different country on short notice is what most often causes a gap. Once a turnaround date is confirmed with the U.S. facility, the support letter, credential evidence and duty description should be finalized well before travel, so the officer reviewing the case at entry has a complete file rather than a promise that documents will follow. 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.