Research Structures
Let's say a research structure needs to be scuttled to free up a logistics "slot" and it is your fifth structure of that type. Do you "lose" any level five techs you have researched when it is scuttled or can you just not research any additional level five techs until you throw another one down? Another way of phrasing the question is if research structures need to be "maintained" at levels in perpetuity or do they only "count" at the instant you buy a tech?
I've been building research structures on other planets to "replace" ones I am about to scuttle, but I realized that I may be unnecessarily overbuilding when my materials might be better spent in those instances on defense. I would then maybe wait until after a successful defense to build back up to the research structures I need.