When do I assist hatch?

[Chickens and ducks]

I am hatching my first batch of duck eggs, first one pipped a day early on day 27 and started zipping quite quickly however has stopped and it's approaching 36 hours with no progress. Should I assist? Temp is stable and humidity has remained between 66 - 70 percent. Photo attached of its current state

 

[WhiteCollarWeezy]

If it has been 36 hours with no activity I would assist...depending on the status of the other eggs inside your incubator....

 

[BoundlessLove]

Yes, I would if it has been 36 hours since pip. If you have other pipped eggs, try to keep up the humidity when you remove this egg. Maybe add a wet paper towel.

Here is an article on assisting:
https://www.backyardchickens.com/articles/guide-to-assisted-hatching-for-all-poultry.72886/

 

[Chickens and ducks]

The others have all now piped and have tips of beaks sticking out. I ended up assisting the one in question, everything looked good however had a small amount of active vessels and is chewing a lot so I only opened the top of the egg and left to finish absorbing yolk. It's now been near 24 hours more and chewing has reduced but they are all still in eggs, all moving and chirping but none seem to be struggling.