Just got word maintenance is running a bit over. Expect another hour-ish, but we'll know more towards the end of that period.
If you are already in-game and don't log out, you can likely still play - the realms are up. If you get disconnected or are trying to log in, you probably won't be able to authenticate.
We'll try to keep you posted.
Thank you for your patience.
Battle.net accounts having this issue seem to need a nudge to update.
Prior posts have outlined a couple ways to do this, changing to PTR - and back.....hitting ad sub, etc. - changing your password may also work.
This is being looked into.
If updating your sub - or changing your password doesn't seem to work (make sure you launch the launcher app fresh), pop open a Live Chat. We may be able to nudge from this side.
As to why we are recommending self-help, it's a WHOLE lot quicker for you and less hassle than having to contact us unless need be :)
I'm also having this issue as well as my main account being replaced with Heroes of the Storm1 in its place, strangely my characters show up but are set to Inactive and I'm prompted to upgrade my account as well as add game time.