I am hatching three pekin eggs. They are at the end of day 28(hatch day) almost into day 29. Candling at lock down revealed three wiggling and alive ducklings getting ready to hatch. I had to do an emergency intervention just a couple minutes ago as the humidity dropped below 45%. While quickly adding some hot water I shined a light into each egg revealing three active ducklings but only two internal pips. (Incubator temp never dropped below 99* and the humidity is back at 60%). I have a duck egg hatching calendar that says the external pip will happen 6-12 hours after the internal pip. When I hatched chicken eggs earlier this year the chicks peeped loud and often after the internal pip. Does that happen with ducks as well? With day 29 starting about 9 am tomorrow, when should I consider assisting with the hatch? What signs should I look for that they may need some help?