David's is an upscale steak house onboard which does cost an extra $30 per person if you choose to dine there.
In my opinion it's well worth the extra $30. Food in Carnival's steakhouses is simply outstanding, and you definitely don't leave hungry.
I don't recall the hours, but generally right through dinner service; opening @6 PM, and seating people to about 10:30.
Perhaps someone else knows the exact hours.
Now you've DONE IT. I got hungry just typing