Beckles, I'm not sure DL has an official policy. I've seen it both ways over the past 3 years. Had a gate agent in SLC tell me "You must wait in the gate area. We will not come onboard to get you, we're just too busy to do that."

Then had an agent at DFW come get me from my bulkhead seat about 5 minutes before pushback
& move me upfront.