Just a heads up, there will be PSN maintenance this coming Thursday evening, at 8PM UK time, or 12PM PST. The maintenance is planned to last until 2.30AM, so don’t plan any online gaming, PSN purchasing or TSA meets for Thursday night.
While you’ll probably be able to remain signed in if you’re already on the network, and you might even be able to sign in during the maintenance, the Store and Account Management will be unavailable, as well as the possibility of Home being down.
There may be additional downtime in the hours after the maintenance for “testing purposes” but the Network should be fine by the time you wake up on Friday morning.
There’s no word on what the maintenance is for, or what it entails.
Source: PlayStation Community Forums