TN itself requires a temporary purpose, so planning a longer-term move alongside it isn't automatically disqualifying, but it needs careful handling. How the two coexist depends on timing, the specific longer-term route being considered, and how consistently the applicant's documented intent matches each stage.
Get specific about which longer-term route is realistic
General curiosity about permanent residence is different from actively pursuing a specific sponsorship or filing. Counsel needs to know which stage the longer-term plan is actually at to advise on timing and intent questions accurately. Vague future interest usually doesn't create the same complications as an active, concurrent process, but the distinction matters enough to discuss explicitly rather than assume.
Underneath the intent question sit the conditions that decide most cases and are sometimes overlooked in a conversation about long-term plans. The occupation must be one of the listed USMCA professions; the applicant must personally hold the qualification that entry requires; the employment must be prearranged with a United States employer or entity, since self-employment is not permitted; and the applicant must be a citizen of Canada or Mexico. A household that has spent months planning a longer-term route around a TN foundation should confirm those four first, because they determine whether there is a foundation at all.