We've frequently seen just one counter open on EMH nights. Don't think they have the hot food though, maybe just sandwiches and snacks.
I would guess they close at 7pm along with eveything else in the Land but Garden Grill and Soarin'. I don't recall the Land ride being open late either.
I find it kinda odd that they would close early, but maybe 6-6:30pm so they can clean up and leave? 7pm is still dinner time for us!