It took Earth ~ four billion years to go from molten rock to multicellular life. Let's take that as an absolute minimum requirement of time for organic life to evolve and produce sapient species (I know, that's a stretch, but just roll with it).
So how ancient can my Ancient Precursors realistically be if by lore they're originated from literally one of the first terrestrial planets with advanced organic life in the Universe, if not the first?
I've read that the necessary elements for the creation of earth-like planets began popping in existence not even one billion years after the Big Bang, but as I understood it the universe was still too volatile back then for any planet to exist long enough without some cosmic cataclysm sterilizing it's hypothetically possible beginnings of life. So when things calmed down enough for 4 billion years of relative peace to become feasible?