Irreversible ones should. If the described duties turn out not to fit a listed profession, the whole plan changes, and dependent applications rest on the principal's case. A spouse and unmarried children under 21 may qualify for TD once the principal's route is settled.
Sequence the household behind the analysis
Clarifying duties usually takes weeks rather than months, which is a reasonable period to keep leases, school enrolment, and resignations reversible. If a spouse intends to work in the United States, that requires its own authorization; TD permits study but does not authorize employment, including remote or unpaid work. Each dependent's specific steps depend on their nationality.
A Canadian citizen dependant is visa-exempt and can be admitted at the port of entry with the principal; a dependant of another nationality may need a TD visa issued by a U.S. consulate first, which takes time and should be started early. A child qualifies while unmarried and under twenty-one, and eligibility ends at that birthday rather than at the next renewal. A spouse who intends to work needs an independent classification of their own, obtained on the strength of their own offer and qualifications.
Do not describe household business ownership as proof that the TN job is permissible, because U.S. self-employment is barred.