agnelson,
I thought US does not allow Canadians to stay (live) in the US for more than 182 days in any calendar year. Am I mistaken on this point?
On a related note, since there is no passport check on exiting US or Canada (unlike most countries in Asia), how would immigration know how long a person stayed? If a person left US and entered Canada, would US get Canada entry information from Canada immigration and vice versa?
agnelson wrote:His departure from US restarts his 6-month clock, just as it would if he crossed the border to
Mexico or canada.
There is no yearly six-month limit for visitors to US; each undocumented entry cannot be more than 6 months. The trouble is the more he stays out of Canada, the more likely the border will question whether he truly is a visitor to US or if he simply lives with you.