Using other people's guidelines is a place to start but ultimately you have to work out the settings that work best for you in your location.Up to 5... not sure what the odds are for the remaining 20 eggs to actually hatch but they get another day or so. Curious if my low hatch rates are from something I’m doing or with my incubator... I’ve had people buy fertile eggs and get 80-100% success rates in their incubator so I’m thinking it’s my incubator/technique? I did follow Porter’s advice for temps/humidity and have done lockdown at the right time and haven’t opened the incubator at all since start of lockdown.... fingers crossed for more babies to prove me wrong.
Only thing I can really think of (other than incubator itself) is the house doesn’t keep steady temperatures this time of year so my eggs in holding to hatch are subject to that.
Here is some information on Common Incubation Problems.