The recommendation is to store them for no more than 7 to 10 days. Ideally around 60°F and 60% humidity while turning at least 3 times a day.
I collect mine for 14 days but have hatched ones that were more than 21 days old. The older they are, the lower the percent of hatch will be.
Guinea...
They definitely know a difference when it goes from 15 eggs down to 2. If I leave 4 fake eggs in a nest, they stick with the nest a lot longer than if I leave one or 2 fake eggs.
If you are concerned, reduce the number of eggs in the nest by one or two a day so it won't be such a drastic change.
If you see a cock standing erect in one spot and looking around, he may be standing guard over the hen as she lays an egg in her hidden nest.
Some people keep their hens shut in the coop until after they lay their egg for the day. It works fine if your guineas lay early during the day but not...