You are going by the incubator's gages then? Most incubators, unless you have spent the big dough for the Brinseas or R-coms, have unreliable gages. For example, the LG 9300 is NOTORIOUS for being way off. Most users have to adjust their temps 1-3 degrees (F) higher just to get the proper temp inside the bator. Best lesson you can learn when incubating is never trust a thermometer (especially those on the bators) that is not checked for accuracy. Always have an independent checked thermometer in the bator (I use no less than 2 and usually have three).
There's not much you can do at this point. A chick has to pip and then the vascsular system between chick and egg has to have time to shut down completely before assisting can be done successfully. Before this occurs,any attempt to help will carry the probability of causeing the chick to bleed out. I lost my very first hatch attempt to a faulty (brand new) thermometer. I ended up with one hatcher that survived hatching out at day 24. (The delay caused leg problems that weren't detectable until later on.) That is why I am so anal about checked (multiple)thermometers. I'm not so precise about my hygrometers because I monitor my air cells for growth to know my humidity is accurate for my eggs, but a checked accurate hygrometer is also a good thing to have as well.
