Good luck!
I ditched my vent plugs after everyone was recommending getting rid of them. I thought it would be harder to maintain humidity, but just the opposite actually. (hatching chickens, not ducks) Of course I have chicks hatching one right after another, so humidity is too high right now. I keep having to crack the lid to get it back into a safe range.
I have always understood lockdown to mean just that. The humidity is going to go hi as chicks hatch.
I vote you go read a good book. Lil
Stop messing with the Bator