Originally Posted by kmersh

I checked in for a flight tomorrow and found OSS on my connecting flight within Canada.

I at first thought it was the dreaded SSSS but thanks to Google came across this thread.

So as I understand things OSS means NADA, ZIP, ZILCH, right now, but in the future means that I could avoid having to be screamed by CATSA as plain old TSA screened me already in the States, is that correct?