I'm departing for YYZ from ORD in a week or so. I'll have plenty of time to kill and so the Flagship Lounge comes to mind. The lounge is at the extreme of Concourse K and most YYZ flights seem to leave from G or H. Is access between the concourses easy, or indeed possible, without tackling security? I used the lounge quite a few years ago but can't remember. Many thanks.