Processing standbys earlier does make it possible for customers to get a main cabin seat and then be eligible for an upgrade 40 minutes out. However processing standbys earlier makes it tougher for a customer to run up to the gate, trying to make an earlier flight, and still get on. Non-revenue customers may be cleared onto a flight ahead of paid customers trying to fly earlier.
I’m happy with the tradeoff because when the algorithm decides who gets the seats I shouldn’t need to worry about rogue agents.