She never went on record as being against TPP until a week before the first debate, after the TPA vote was already in the bag. And even her "opposition" was typically mealy-mouthed, giving her an "out" by saying she "would not be in favor of it" instead of actually saying she outright opposes it. She is on record for promoting TPP dozens of times to different audiences, claiming it "sets a gold standard in trade agreements". And the concerns about TPP that were being expressed when she was calling it a gold standard are still concerns that are being expressed. She did not learn anything new about it-- she just saw which way the wind was blowing.