Originally Posted by
maggersmagoo
Is it still possible for someone with a higher priority to come in and bump those top two out, even though there are seat numbers assigned? ...
No, they have confirmed seats / upgrades.
There are a number of other things to mention
The list you see is only used at the gate but there is another similar (but some differences - take a bit to explain all the differences -- see the new thread's wiki)
Those with the checkmarks may have been upgraded earlier or more recently. They may be CPU, they may be supported upgrades.
Other seats may have been taken by last-minute purchase / flight changes or by folks do cash upgrades or ....