User blog comment:TheScottBird/The Continuity Error/@comment-5899967-20140612214439

It could be just Gwen for all we know, she is the only one who claims that, everyone else still calls her "the new Heather" as of Heroes vs Villains.

The creators could have done that to make Gwen look less of a villain (if they really have retconned the story), because she is one of the protagonists in TDAS.