No there is an upgrade standby list and a flight standby list.
Regardless, what in the world is your question?
I am booked in J on a afternoon flight for tomorrow, DL put me on standby for an earlier flight, I am the only one on that list, but there is a upgrade standby list as well. Now, at the gate where there will be some empty seats in J, who will clear first, I as someone who paid for J or people on the upgrade list? Hope this is clear enough