for smaller things like DL expiry, they have used the machine and then been sent to secondary solely to provide the new info
The first time I had to deal with a DL renewal (though still in the period of the old one), I called Champlain to check their hours. They said we could just fax them the new DL with a covering letter. I did that and we've had no trouble crossing (at Champlain) since then. DL expiry was July 07, sent the fax in June 07. I assume something important like TN status wouldn't qualify for faxing, though I don't see why not.
=aw