I am just now filing for my OPT post completion authorization and realized that the processing times will be such that I could be OPT-less by the time I start work. The TN visa is also an option for me so in the worst case, I would just apply for the TN at the border.
However I was wondering if it was possible to do a change of status from TN to OPT after my OPT gets approved/arrives. Also, will the government deny me of my OPT if I am already on TN? Thanks.