This may be or may not be a bug, but it surely is annoying. In several of my past games I would invariably reach a point, typically within 5 years, where something would happen way out in the void of space. . . and suddenly my time increments are limited to 1 day sub-pulses.
At first I thought I had misclicked, but then it continued even when I knew there was no error on my part. After a little less than a year of this day by day toil I bowed my head in defeat and made a new game. Much to my chagrin I found my time slowed again, this time within the first year. My eyes narrowed and I thought, "What is this nonsense that plagues me?" For a third time that day I found myself looking at the Create New Game screen, wondering what it could be that was causing my time to slow. This time I left everything set to the default, knowing in my beginning games nothing like this had ever occurred.
Before I started, though, I read through the forums. Searching reading the most relevant posts should they already contain the answer to my mystery. Most of the suggested causes were NPR combat, or possibly even an Precursor ship spawned in the same system as an NPR. But in my case the time was consistently 1 day at a time, never any 5 seconds of combat spam. Finally I read somewhere to turn on space master and read my events and by the gods did I find my answer.
Going back to my original two games with this issue I found that spacemaster as limiting time to 1 day as I had expected, but it was because of an incoming fleet. For 340 days a fleet had been approaching someone, the same had happened in my second game. Further investigation revealed the source of the issue to be Extra-Galatic Invaders, which is disappointing because I wanted to see/fightbe horribly murdered by them. So should I just disable them until mid-late game then. . . well wait I guess?
TL;DR
Extra-Galatic Invaders seem to cause some rather intense waiting periods when they're flying to wipe someone off the face of the universe. Can I make them go any faster or just leave them disabled until I want to suck it up and wait?