Just called again. Figured out that saying "agent" or "operator" is the (undocumented) way of getting a live person out of the automated reservation system.

The live person said his name was Jeff and had an Indian accent ( you'd figure that if they had their Indian call center people use non-Indian names, they'd also have them go through accent concealment training). Unlike the Indian call center bashers' experiences, I didn't have a real problem understanding, nor did he. However, he said that the seating was under airport control and that no seat assignments were given until 48 hours before the flight. .

The flight is on a tuesday to a lightly traveled destination (there were plenty of seats available on a similar size regional jet on the return trip on Delta), so it seems hard to believe that it is a very full flight.