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I read a series of novels in the 1990s-2000s where a world was colonized from Earth by slower than light travel. Eventually, FTL travel was invented and the world changed dramatically (I remember there were camps where living conditions were poor). I seem to remember that there was sabotage of a ring that was being constructed that would have led to even more migration. I’ve been looking for the series for years. Can anyone point me in the right direction?