40 unhatched eggs?
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Guinea eggs normally take from 26 to 28 days to hatch. Unfortunately they like to sit on large clutches of eggs and if it is only one hen sitting on 40 eggs, she can't cover them all properly. If she has been sitting for over a month on a huge clutch, they most likely aren't good anymore.
I would clean out both nests and let them start over. With guineas it usually doesn't take much messing with their nests to get them to abandon the nests.