because the FDA lowered its standards—perhaps in response to Amphastar’s high-profile lawsuit against the FDA
Well in Amphastar's lawsuit, they said that they had already achieved "sameness" under the FDA's 5 criteria. So that implies the hard lifting had been achieved prior to the lawsuit.
My bet with you is still to be determined - it was Teva-specific, not based on any generic. Around another 2 years to run I believe.