This advice comes from the fact that firmer, greener fruits typically take about five days to ripen at room temperature.
As the event approaches, the avocados should reach ideal ripeness. The nutrition site guides
It adds: "Ripe fresh avocados that yield to gentle pressure should be eaten within a day or two.
For events that are four to five days out, purchase firm avocados instead. Unripe, firm or green fruit can take four to five days to ripen at room temperature
Moreover, they caution: "Just be careful to watch the fruit to make sure the temperature in your kitchen does not cause them to ripen too quickly.
If they begin to yield to gentle pressure, place them in the refrigerator to slow the ripening process.