If the meringues are a little chewy after baking, it means they aren't fully cooked/dried out. You can put them back in the oven for 15-30 minutes to harden.
You can bake the meringues a day (or a couple days) before serving, so that all you have to do right before serving is assemble the toppings, making for an easy dessert for dinner parties.
The total time doesn't include the time in the oven, after baking, when the meringue is cooling/drying out.