The PlayStation Network will be going offline for scheduled maintenances early next week for a total of nine and a half hours. The maintenance window begins at 2:30 AM GMT / 7:30 PM PDT on Monday, 11th May 2015, and finish at 12:00 PM GMT / May 12, 5:00 AM PDT on Tuesday, 12th May 2015.
The maintenance window cuts into your evening gaming session if you’re in North America, but for once, it won’t affect Europe too badly, unless you’re a morning gamer.
As usual, online gameplay is available during maintenance, but only if you have recently signed into your account with that system (within past 24 hours for PS4).