How many bodies do you have? A 727-200 freighter has 12 positions main deck. Four or five guys working there, one driving the K-loader, someone at the bottom of the K-loader and a couple of tug drivers with strings of dollies staged by the wing should be able to download a flight with no oddball pallets in 20 minutes and upload about the same. You get a double overhang or a 9000 pound pallet having a bad day, all bets are off. The bellies are loose loaded but the isn't much room so a couple of guys should be able to do one in 15 minutes.