Hi, I sent my passport today to Ottawa for TRV stamping via UPS. I saw that it is required not to use a private courier for the prepaid returned envelope and I need to use xpress post. One of the workers in UPS told me that it is not necessary and he recommended me to use UPS as a returned mailing to my residence in Canada. He said that many students did that and it came back so fast. What do you guys think? Did it make the wrong choice? Thanks