Its short duration does not itself authorize work.
Confirm actual permission
A business deadline or limited weekly commitment is not an admission decision. Review the relevant authorization before performing the activity.
A Canadian citizen can apply at a port of entry the day the file is complete and, if admitted, begin work immediately, so the timeline is set by how quickly the supervising professional's letter and credentials are assembled. Preparation should begin as soon as the turnaround schedule is confirmed, since port-of-entry processing depends on complete evidence being ready on the day of travel, not assembled after arrival. Allow extra time compared with a straightforward single-employer case, since the structural review itself takes real work before any filing timeline starts. Review current entry procedures before booking travel, and if the employer, the duties, or the assignment changes, ask for a fresh review rather than assuming the original plan still applies. A hiring deadline does not establish direct professional support or authorize work, and a generic letter should not substitute for facts the employer has not decided.