I was on Enchantment last month. They had shows at 7 p.m. and 9 p.m. The 7 p.m. show was for the late dinner seating (8:30 p.m.). Since dinner was typically running 90+ minutes, we were never able to make the 7 p.m. show and had to do the 9 p.m. late show.
I think they space it so that everyone is freed up for the activities later in the day in the other lounges.
Enchantment - August 2005