We haven't dined that late at Akershus but we have at 1900 Park Fare. We weren't rushed at all in fact I think we ended up with extra character interaction because it wasn't busy.
At 1900 they don't serve lunch but it is IMO the same basic gig. At Akershus they do a seating of the restaurant, serve the food, the place cleans out or most of the way - is all cleaned up then they seat another round. You'd be in the late breakfast group but you shouldn't be rushed.
Go and have fun!