It has been a while since I've thought of this: There were so many transitions between TNG's 1st and 2nd season - The bridge went through minor modifications, specifically the Conn and Ops chairs, Picard's armrest interfaces and the panels on the sides Geordi and Worf got promotions (say what you want, the change in Worf's uniform from red to yellow indicates to me he was not formally placed as head of security/tactical until Season 2). Riker, Troi and Wes all went through changes in appearance. Beverly left for Starfleet Medical. I don't recall that there was ever any real "tales" of explanation of all this happening. I know that other than "The Child" when Pulaski came on, and Geordi was in charge of the plague strains, we didn't even reference anything on screen that I can recall. Does anyone recall anything about this other than what I've mentioned, either on screen or in print?