Good luck with your hatch! Quail are fun to hatch.
Be careful covering an incubator, that you don’t block any vents or cause it to overheat.
I won’t say “always”, but most times I would choose to pop the lid enough to add water, than to let humidity drop to 40% during hatch time.
I have several incubators. My Brinsea Octagon Eco had the most trouble keeping humidity up, so I took a piece of quilt batting material and draped it thru the channels and across the bottom, under the hatching tray. It wicks the water from the 2 channels and spreads it better so it does maintain humidity better.
Depending which one you have, you may try something similar, or pop some damp sponges in there. They will bump it up too.
Sorry, I took this after a hatch so it’s dirty, but here’s what I mean
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