i sit down most mornings and glaze 5-10 units (some with a stain fire) in about 2hr. this includes phone and employee interruptions. but glazing has come a loooooong way and is far easier than it used to be. if i had zero distractions and interruptions the total amount of glazes i could do in a day would be a fair number.
veneers are more tricky, so maybe i was a bit high on 25-30....but 20 should be easily attained in 8 hours. seriously 10 on a tray for a stain fire, and in the oven. then fill another 10 on a tray for a stain fire. total time ~2-3 hours? or less? then repeat for glaze fires on both. easy IMHO