Yep. You can only run a given operation once a week in a given difficulty setting. You cannot do story mode EV again this week. You can do EV in hard mode. You can do Karagga's Palace. But you can't to EV again until tuesday.
thanks, follow up question - last night I joined a PuG for EV HM and we got to SOA 10 mins before maintenance so they called it. My lockout now shows everybody but SOA in EV HM, but since it was a PuG how do I finish this? Will I be allowed to join groups that are starting before SOA? Or do I have to form a group exclusively to finish SOA?