I returned some syndicate plans to the person in Nar Shaddaa promenade area.
However, I have no idea how I had to got them in the first place. I just recently returned to game and have not played since about february, and noticed I had some of those syndicate plans, and found out that I can return them to nar shaddaa for reputation so I did.
Now I have been back for a while and havent got any of them ever since, and it seems I wont be able to get any more of them since any of my characters does not have the companion and its not obtainable anymore, except from collections for those who have had it in past.