Many individuals on their initiative, or based on advice, head down to the Border to renew their temporary resident status in Canada. This is, many times, a bad idea (unless you're an American, preferably a NAFTA professional).
Consider what happened in Nicole Marie Dolan (Download Dolan v PSEP).
To put it politely, Justice McVeigh called the Border Officer "overly enthusiastic" in her zeal to find any infraction, real or imagined. Had the decision stood, a couple would have been separated for no more reason than the fiat of an officer. Luckily, and while the application was ultimately dismissed, it achieved the result that we needed, which Justice McVeigh directing that the Applicant not be prejudiced for not attending for a further interview as directed; that a new dated should be provided with the understanding that she could provide additional information and documents addressing the concerns raised by the first BSO; and (this is telling) that Justice McVeigh "suggest" that a different officer conduct that interview.
Remember, the Border happens to some kind of singularity where ordinary laws do not seem to apply. There is no right for counsel to attend. They can go through your phone or laptop or other electronic device. They can search your car. All for inciminating evidence sparked perhaps by their motivating confirmation bias that you are in breach of your work permit, or are working when you are not supposed to, or haven't acted the way that they think a visitor should act.
Once they've confirmed their bias, the damage is done, they will present you with two options. Neither good. One is the sugar coated voluntary departure, where you can leave and they will assure you that it won't impact your future entries to Canada (ha!). The other is that a removal order will be issued against you.
The option to review such a removal order issued at the POE? An application for judicial review at the Federal Court. Contacting the POE to speak reason, and explain misunderstandings, unfortunately, has not worked well in our experience. That being said, our most recent issue at the land POE may in fact be resolved without the "nuclear" option. A manager has graciously responded to our email in support of a family that is facing removal and has assured us that they will be afforded every opportunity to address the concerns of the officer.
...but man, proud man,
Dress'd in a little brief authority,
Most ignorant of what he's most assur'd—
His glassy essence—like an angry ape
Plays such fantastic tricks before high heaven
As makes the angels weep; who, with our spleens,
Would all themselves laugh mortal.
Measure for Measure Act 2, scene 2, 114-123
If you are thinking of going to the border to renew status, ask yourself why. If what you seek can be done through an in-land office, that should be your first, second and probably third option.