Furthermore I took an online assessment and went through the different options they had to see if I was eligible for extension. There was an option where they stamped my passport with a date, and an option where they left it blank. When I visited before, I received no stamp the first time. This means, I am assuming, that I could have stayed 6 months (??) before I was over-staying. Please correct me if I am wrong. Half way through my visit we drove to seattle and then back through the border. I received a stamp with a date for the day I went back into canada. Under the stamp he wrote another date, which was my return flight that he asked about. The date on the stamp I assume is when I came in, but if there is a date underneath... if I stay past that am I... expired? And if so, 30 days before this date, do I have to apply for extension?