I still have this issue, but it varies from application to application. Konsole is the most problematic. When logging in, KDE remembers which workspace I was on, and remembers all the instances of Konsole in the session, but puts all those konsoles at the active workspace (so I have to manuall spread them around to their intended workspaces). Loggin out and back in, and the konsoles are once again gathered at one workspace (the first one displayed). Some other apps works as intended: Deluge-gtk opens at another workspace, the correct (remembered) one. Kmail, however, doesn't restore fully, just as a letter icon in the indicator bar.
I still have this issue, but it varies from application to application. Konsole is the most problematic. When logging in, KDE remembers which workspace I was on, and remembers all the instances of Konsole in the session, but puts all those konsoles at the active workspace (so I have to manuall spread them around to their intended workspaces). Loggin out and back in, and the konsoles are once again gathered at one workspace (the first one displayed). Some other apps works as intended: Deluge-gtk opens at another workspace, the correct (remembered) one. Kmail, however, doesn't restore fully, just as a letter icon in the indicator bar.
Ubuntu version: Kubuntu 15.10 wily