So a while back ago I got a b2 visa to travel the US, stayed for around six months, had a great time and made plenty of friends. This is a 10 yr visa so now I have to use it any time when entering the US. So fast forward to now and my travels have taken me to Canada on a 2 yr IEC visa, which is awesome. However I spent a few weeks in the US to visit friends before I entered, and the border officer stamped my passport with another six months, expiring March 2017, even though I explained I would only be there for a few weeks.
Obviously I won't be spending any long term stays in the US now, but should I want to nip across the border to visit friends, how will this affect me in the case of:
A) returning before March 2017, so when my visa is still valid. I believe it's multiple entry? (Unlikely this will happen but you never know)
B) returning after the six months have expired, say April 17. Will this be an issue as technically my visa will have only just "expired" even though I was only in the country for a few weeks in Sept?
C) Does residing in Canada count as leaving the country in visa terms? I know it doesn't on an ESTA, but I'm presuming the customs officer would have told me if this was an issue as he knew of my travel plans.