I just went through a hatch where the power went out on day 10. It was out most of the day and although the house stayed warm it is still quite cold here and the incubator thermometer read 72 for several hours (like 6). As per Gail Damerow's instructions I figured that too much intervention might do more harm than good. When the power came back on the bator heated back up and so far 10 of the twenty eggs have hatched. Several hatched with crooked legs and feet but they have all pretty much streightened out as the chicks have been walking (stumbling, crawling) on the mesh of the incubator floor.
There are still some eggs hatching now on day 22 so obviously the hatch is delayed somewhat for some eggs, although not all. The last chick hatched so far was strong and normal although a little late.
I would carry on as if nothing had happened and be very slow about declaring the hatch finished and over so you don't lose any perfectly good stragglers.
It ain't over till the fat lady sings...
