I am one of those nuts that spends vacation time watching the chickens. A few years back I followed several hens for almost three weeks as they laid eggs into nests they ultimately began incubating. Time of day varied greatly, even for a given hen. Interval between eggs of a given hen was very important. Young hens in their prime produced eggs on intervals as short as 23 hours which caused each successive egg to be laid earlier in the day. When laying time would be during darkness, then a day was skipped to reset schedule. Some layed with longer intervals. Some even where erratice.