Can't play BG w/friends -- "Party invite is no longer valid"

For about a week now any time my friends and I try to play Battlegrounds we get the “Party invite is no longer valid” error. We’ve seen this a lot but usually after we all restart our clients or BNET entirely it lets us make the lobby and start the game. These fixes no longer work however and no matter how many times we try or restart the game/bnet client/our computers it simply will not work.

What more can we do? Or are we just boned and playing BG with friends is broken server side? I haven’t heard anyone else complaining about it so I imagine it’s not widespread. There’s three of us and we have tried inviting just one other player at a time, changing the initiator each time and the problem is affecting all of us, not just one.