i went into the bumbles store and ended up with a couple of little buttons premium naps and the pop naps to put inside them. didn't really work out that well because the snaps would dig into charli's thighs
but that's what the lady in the store recommended to save a few $$$ and get more out of them
i've since sold the 'insert naps' and kept the premium naps as they are great!
i'd certainly recommend giving pop naps a try on a bub of olivia's age, but don't try and use them with premium pockets....get the proper pop nap and pop cover

they are basically another version of using a cover and prefold, which works really well on young bubs
hope all that makes sense!