And one thing I noticed...if the main page has times, that means there are openings. If you go to the specific restaurant page, you will sometimes find additional times that would be more convenient. Like the main page showed me 845 and 1010 for a breakfast, but on the 1900 Park Fare page, it might show 820 and 900. I think it's like the "Disney Picks" for your resort...they are trying to fill up the times with the most space.
But if the main page shows no tables, I have found that that means no tables.
At least on my computer. With my browser. Who knows what others are seeing?