We can do 50 birds in about 3.5 hours. There are four adults (one killing, scalding, and plucking and three eviscerating), and two children (they check for pin feathers, remove the oil gland and feet). We do have a tub plucker and a whizbang scalder. We only have two cones though so that slows us down a little. I think when our two new people get a little more experience and we get a couple more cones, we should easily be able to get through 50 in two hours.
When I plucked by hand, it took me at least 15-20mins just for plucking. I am a slooow plucker by hand.