I have an older version of the 1588. It doesn’t look anything like that. Wow! They have seriously changed things and made it easier.
First I suggest you calibrate both thermometer and hygrometer or get new instruments that you can calibrate. Do not trust any instrument that comes with any incubator of any make or model. They are unreliable. You need to know what you are working with. These might help.
Calibrate a Thermometer
Rebel’s Thermometer Calibration
Rebel’s Hygrometer Calibration
You are getting conflicting information on humidity because there is no one perfect humidity that works for all of us. You would think that the conditions inside the incubator at a certain humidity would be the same for all of us but for many different reasons it’s not. You would think that each chicken egg would need the same humidity during incubation, but that’s not true either. The professionals that hatch maybe 1,000,000 a week in incubators that hold 60,000 or more eggs each have to tweak the settings on each incubator to get them at their peak efficiency. If they move one incubator to a different position in the same incubation room the tweaking has to start over. They do that by opening enough unhatched eggs to try to see why those eggs did not hatch and adjust humidity accordingly.
Luckily there is a wide range of humidities that do work, but it may take some trial and error to find your particular sweet spot. For some people that may be below 30%, for some it may be above 50%. Mine is about 39%. I’s not about an instantaneous humidity, it’s about the average over the 18 day incubation period. It’s about the moisture loss over the entire incubation period. I’ve had great hatches where the humidity peaked at 50% for a while and I balanced that with 30% to get an average around 39%.
What I suggest is that you settle on something, either high, low, or in the middle. Keep good notes during incubation. When the hatch is over open the unhatched eggs and try to determine if your humidity should be higher or lower. These troubleshooting guides may help with that. There are a lot of things besides humidity that can affect the hatch, it’s not always easy to figure out what the problem was but we can just do the best we can.
Mississippi State Incubation Troubleshooting
Illinois Incubation troubleshooting
As for humidity during lockdown, again different people have different opinions and have different results. I shoot for somewhere in between 65% and 70% but after the chicks start hatching it’s pretty normal for the humidity to jump up to 85% or even 90%. That difference does not seem to bother the late hatching chicks at all, at least for me. I’m not convinced being precise on this is all that critical as long as it is high enough.
Good luck with it. I sometimes make it sound harder than it is. There is a fairly wide range that you will get chicks to hatch, often a lot of chicks.