I taught early morning seminary two different times in different states, one year in each location.
I can't count the number of times I fell asleep in the recliner with a bunch of books on my lap. There were also a few times when I got up in front of the class not knowing exactly what I was going to teach because I had no time for preparation.
On days when there was no school but I still had to go to work it felt almost like a vacation day.
Oh, and there is NO comparison between early-morning seminary and released time seminary with professional teachers. The sacrifice kids make to attend true EMS is remarkable.