U.S. CBP pre-clearance office in Dublin has informed AILA that in situations where a CBP inspecting officer has not admitted a TN visa applicant for the full three year period of stay requested, the TN visa worker may “in theory” seek to correct the admission period at a CBP Deferred Inspection office in the U.S. AILA Rome Dist. Ch. / CBP - Dublin Meeting, Nov. 10, 2011, AILA InfoNet Doc. No. 11121461 (Posted 12/14/11).
The Dublin office also advised that to avoid this issue, TN visa applicants should carry a copy of the TN visa regulations when applying for TN visa status and to be prepared to discuss the issue with the inspecting officer. Id.