We flew U fare on PEK-YYZ route last week. We confirmed the upgrade when we bought our tickets long time ago.

At check-in, the agent gave us BPs in J.

At the gate, we handed in the BPs and SWUs. But the GA refused to lift the SWUs.

Anyone knows what happened? Was it just the GA or could it be something else the check-in agent did or didn't do? Or were we just lucky?

I am just wondering if there has been any case where the GA won't lift the precious SSWUs at boarding...