Well, I might as well share our experience at the border.
We decided to go to the Coutts border crossing as we wanting to have lunch in the U.S. and do some shopping.
We got to the border and told U.S. immigration that we wanted to do lunch in U.S. and then my wife would land. They told us that we couldn't do that as my wife would have to do the landing first just in case 'the landing didn't go well on Canada side.'
We accepted that and went into the office where this lady was at first a bit surly to us but then was fine and polite. My wife got the form and then they showed us how to get back to Canada's side.
At Canada immi we told them my wife was going to do her landing, they said 'fine' park at the parking lot and bring all the paper in.
We got in, gave them my wife's passport and her refusal letter from U.S. immi, for some reason they took my passport too.
After a long wait, and I mean LONG (50 MINUTES), they called us to the counter were the immi worker gave me a lecture about why we didn't make an appointment at the CIC office in Calgary. I was honestly surprised and taken back by this. After a bit of the lecture, he said that we weren't in trouble, just he wondered why. I said that we got the papers late Thursday night and this was the fastest way to do her landing. He did seem quite annoyed at first, but then his attitude did improve a bit after the lecture.
After that, he took her COPR and then said that he had some work to do, and told us to go sit down. After about 5 minutes he called us back up and then read over the document with my wife and told her to initial and sign at certain places on the form and made sure she was aware of the rules '2 years with me' and the '3 out of 5 years' in Canada. stuff.
He then told us to sit down again but called us back quickly signed and stamped the form. Also, they told us that my wife couldn't go to the U.S. until she got her PR card. Said we couldn't use the COPR for 're-entry' and if we did go, she would need to visit an Embassy to get a special PR document to prove she is has landed and is a permanent resident of Canada. He told us just to wait until she gets her card in the mail.
All in all, it took about 90 minutes at both Immi offices.
I wouldn't got to Coutts as it was a busy immi office, , which probably slowed down the process a lot and the workers weren't very polite tbh.