My character was in the Wither and Decay raid instance, character was removed from expedition, but stayed inside instance. Eventually I could not send any messages, but I could still read everything others were saying. Finally, I was disconnected (no connection issues) and when trying to get back in, it showed my character as still in the zone, but it kept saying the zone (Demiplane of Decay) was unavailable. It took a while, but eventually it let me back in the world. It logged me in at my bind point (Guild Lobby). I had zoned into the instance from Crypt of Sul. Raid expedition was filled after character was removed.