Likely due to a wide range of labour issues with both CATSA and contractor (Garda) management. CATSA is trying to shake things up across the country right now by arranging the contracted companies (which had to go through a recent bidding contest) into regions. This is presumably to take a tougher stance on the companies who are beginning to stand up to their bureaucracy. Garda will be the contractor in YYZ/YTZ for the foreseeable future, but between now and November 1, and possibly beyond, will be a turbulent time for airport screening in Canada. There was a major unrelated development in this industry recently on which word started trickling out today, but I won't reveal it for fear of government/private retribution. The important thing is that things aren't gonna be any easier for a while!

I'm actually impressed by this. The CATSA screeners' union in YYZ (Canadian Airport Workers Union) has traditionally been pretty spineless... maybe a few disgruntled union stewards started this.