Big advantage in my opinion. Not only they will be fresh but also they will have more time to prepare and improve whatever they need to improve during this break even if I think they are solid in all areas. I don't think Napoli will cease any of those players until next summer and if they will win Serie A , I think they will sell none of them until they have the UCL run after winning Serie A. However, I'm sure a lot of important and respectable clubs are already watching they "brains" of Napoli from the pitch.