How long before I help a chick hatch?

[Monilor]

All of my babies hatched on day 21 and day 22. I have 16 eggs that haven't hatched (13 have...my first time so I'm happy with that).
I just candled the rest and there's one who's beak is moving and she's in position where her head is by the air sac.
How much longer should I wait? All of my chicks were put into the incubator on the same day at the same time.

 

[Poultrybreeder]

Watch the progress on the eggs, go back and check again 3-4 hours later, if they have not progressed, you should probably try to help them

 

[Pyxis]

You might try putting a small hole in the air cell using a small sharp screw or drill bit. From there, you can look in to see if they are alive, internally pipped, etc. Alive chicks you will be able to see moving under the membrane.

If you do find one that is internally pipped, let it be for a couple hours before proceeding further. I usually like to wait at least 18 hours before I assist, but since you don't know when the internal pip was, just go with what you see. You can open the egg over the air cell with no danger. Apply something like coconut oil or neosporin to the inner membrane to keep it from drying out. Getting it wet like that will also allow you to see if there are any active veins. Hopefully with the air cell open, it will be able to push out on its own when it it ready.