I candle over 2000 eggs every year and I have seen enough that start developing late that I don't even bother to look for ten to fifteen days. At that point there is no denying they are developing or they are not going to. I don't understand the rush.
I don't really rush but if I can see the pencil eraser and spider web it's an efficient way of using incubator space. If I can't see anything on day five I wait til day 9 or so just to be sure. If I get busy sometimes candling gets put off but I don't toss anything if I don't see development on day 5.
