Edit 2: Many people online reporting it's back and can now log in. No word from Sony but seems to be working again.
Edit: Playstation have yet to acknowledge reports of interrupted network connectivity. Some users are disconnected for mere moments whilst others are having ongoing issues.
Hopefully it will be a very quick fix but I'll keep updates in the OP.
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Original post: First time I've logged in for about a week: "PSN is currently undergoing maintenance".
Edited by Cazzy on August 26, 2016 4:05PM