I had egg in lockdown that were Due Sunday. I think one or two hatch by monday. I candled the eggs and they were still moving but only a few internal pips..... Tuesday a few more hatched..... today a few more hatching and some still just pipped..... I don't know what happened but they were all set the same time. My temps must have been lower in the bator and I KNOW they were a little lower in the hatcher but still in the 90's should not have been 4 days of delay in hatching.
I will say most of the eggs are not looking too good so something happened bigger than just a temp drop..... IDK.
First, when do you start counting your days--------the day you put them in the incubator or the next day/24hrs later as day 1?
Having 1 degree difference makes a difference in when your chicks will hatch------2 or 3 degree's makes Alot of difference and is not good for some/most of them.
I know you wanted to see what was happening in the eggs since they did not hatch on time and most people would, But In My Opinion opening the incubator to remove and light the eggs can/could create more problems---so alot was against them.