How long after an egg starts chirping will it hatch?!!! HELP!

[P0U1TRYP3RS0N]

I thought maybe the eggs were too old...because its a little late and um...nothing doing. Humidity at 16% (not sure where all the water goes, but it can drop from 60 to 30 overnight), and I figured they were shrinkrwapped. So I opened the bator..and picked one up..and it started CHIRPING AT ME!!!!
I immeaditly set him back in there.
HOW LONG DO THEY START TO CHIRP BEFORE PIPPING? That means if they're making noise they're def in the air cell right?
And I added water to the trays...but its prolly not above 35.

 

[Elite Silkies]

They should have pipped the air cell if they are chirping. I would give them another 24 hours or so. You can mist the eggs with warm water to keep the humidity up.