Hatched out 16 chicks over 13 days in incubator, but....

[zoo2u]

One of our cochins was laying on eggs and the same thing happens every summer, all the other hens lay their eggs under her as well creating lots of different hatch dates. in the past, i always try to save the eggs she leaves by putting them in the incubator and never had success. I am tickled to say that this summer, it worked. i put over 30 eggs in the incubator and so far have had 16 chicks successfully hatch over the last 13 days. Today, it seems my luck might be running out. Two pips, then nothing all day or tonight and they don't peep or move. i estimated that i needed to run the incubator another week and a half to give all remaining eggs a chance but now i am wondering if perhaps this is it. Anyone ever have experience with this many hatching over such an extended time frame in the incubator. not sure if i should keep it running....