I can confirm that 1 is prioritized before 2. Last year when I was still an SE I showed up at the gate in YYC and asked to be put on standby to YEG as I was on a Flex fare. Agent refused saying "very long list, you'll never get a seat." I walked about 20 steps away and called the concierge, who added me without a problem. A few minutes later I was paged and a different GA gave me a new boarding pass and I boarded the flight.

Once on the plane (which was now delayed too) I found out that the reason for the long standby list was that the FRA-YYC was severely delayed and that a large number of pax had mis-connected to YEG and that all the flights were already at capacity for the day. Shortly afterwards, the GA came on the plane saying I had to take my original flight and that I shouldn't have "gone around" her to the concierge. I thought about standing my ground, but by this time it was apparent that the new flight would likely depart after my original flight so decided to get off the plane in a hurry (it turned out to be a good decision).