The introduction of OSS but not making it available to all international origins is very annoying. Currently at YUL having just arrived from MEX en route to CAI. There is no one at the security check we need to go through so we just have to wait (15 minutes and counting). This also happened last month at YVR, which was even more frustrating because I was connecting to MEX from FRA so should have been OSS eligible but the lady checking boarding passes admitted it was her first day and wasn't familiar with the rules so was sending me through security "just in case".