I delved deep into the forums and my own memories, and it seems as if Ljuboss was (re-)promoted after Kronos and Sauron already became full moderators, with the earliest I could find dating to August 2013. I vaguely remember him still being a pre-moderator when he was in RedDagger on the RP server too, so this checks out. He likely got promoted to moderator in September or October since all pre-mod phases were short this far back, and I seem to remember being a bit surprised on how quickly his went too.