Okay! Here it is. We use the numbers as a guide line. Get as perfect as possible. Then........Things start to happen. Ups, downs, hundreds of things can go wrong. And yet, we get fuzzies. Maybe not as many as we hoped. But at times, Many more than we diserve. The blessing of any at all helps me atleast to try again, and again.
If you count one way or another, your babys can and sometimes do go until day 23-25. ect.
Expect only one thing as constant. We simply put, TRY our very best to mimic what a hen already invented. And they don't get it right some of the time either.
But as a guide line for me, the day I load the bator I do it before noon. Day 1. I candle on day 7, and again on day 14. Day 18 lock down,popcorn, comfie perch, camera and phone. I haven't had a 100% hatch rate this year but it is my goal. Until then, I practice my math skills, hatch again.