Sony just announced that the PlayStation Network will be down for maintenance on April 24, from 10pm PT to 11pm PT. Only the PlayStation 4 will be affected during this one hour of downtime.
“Anyone who already has an account can still sign in to their PlayStation Network Profile, play games, and use most applications while this maintenance is carried out,” Sony stated. “You will not be able to access PlayStation Store and Account Management during this maintenance. We apologize for any inconvenience.”
Most games and third party services can still be accessible if your PlayStation 4 is activated as your primary console. To do so, head into [Settings], then [PlayStation Network/Account Management] and [Activate as Your Prmary PS4], then select [Activate].
Sony will be performing “routine maintenance and improvements” during the scheduled time.